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Europhysics news

Physics of Intercalation Compounds

Hirohiko Kamimura

Published Jan 1, 1982• 91 citations
Publisher

Abstract

The Summer School on Quantum Optics, the last of which was organized by J. Held, J. Czub and M. Gil of the Universi ty of Gdansk, at Cetniewo, Poland from 1-8 September 1981 has become a traditional event for young physicists from eastern and western European countries to discuss recent developments in their fields and to keep in contact.At Cetniewo, about 80 students and scientists from seven coun tries met at the well-appointed sports train ing centre on the Baltic sea.Three main subjects had been chosen and there were presented by lectures at sessions covering respectively experimental and theoretical aspects.(1) The quantum theory of electromagnetic fields and their interaction with atoms and molecules were highlighted in a series of lectures which included light-induced collisional energy transfer and changes in ato mic eigenstates by off-resonant monochro matic light.It was shown, that the emis sion spectrum of a resonant-excited two level system contains sidebands at the atomic Rabi-frequency of the laser field.Coherence and saturation phenomena in photoionisation and different aspects of optical bistability were also treated.(2) Recent experimental developments in quantum optics and atomic physics gave special emphasis to the spectroscopy of Rydberg atoms.New results of double resonance experiments on high levels in in dium served as an example to demonstrate the remarkably good agreement between theory and experiment.The use of ther mionic diodes in experiments on lithium have allowed the determination of ground state isotope shifts, which had not been detected in Rydberg D-states.The possibi lity of using sensitive Rydberg-spectroscopy for the detection of infrared photons was discussed.Another interesting subject was trapped-ion spectroscopy.Very high precision experiments in different laborato ries on hyperfine splittings have successful ly demonstrated ion cooling, which was discussed in detail at the school.This ses sion was completed by a lecture about X-ray polarisation in atomic collisions.(3) The third session covered reactive colli sions including the basis and recent results in chemiluminescence, chemical lasers, in vestigations of collisional energy transfer in vibrationally excited molecules, reactive formation of molecules in collisions and molecular beam scattering from solid sur faces.

DOI
10.1051/epn/19821302008b

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IX-Summer School on Quantum Optics

Günther Werth

C o m p o u n d s The Summer School on Quantum Optics, the last of which was organized by J. Held, J. Czub and M. Gil of the Universi ty of Gdansk, at Cetniewo, Poland from 1-8 September 1981 has become a traditional event for young physicists from eastern and western European countries to discuss recent developments in their fields and to keep in contact.At Cetniewo, about 80 students and scientists from seven coun tries met at the well-appointed sports train ing centre on the Baltic sea.Three main subjects had been chosen and there were presented by lectures at sessions covering respectively experimental and theoretical aspects.(1) The quantum theory of electromagnetic fields and their interaction with atoms and molecules were highlighted in a series of lectures which included light-induced collisional energy transfer and changes in ato mic eigenstates by off-resonant monochro matic light.It was shown, that the emis sion spectrum of a resonant-excited two level system contains sidebands at the atomic Rabi-frequency of the laser field.Coherence and saturation phenomena in photoionisation and different aspects of optical bistability were also treated.(2) Recent experimental developments in quantum optics and atomic physics gave special emphasis to the spectroscopy of Rydberg atoms.New results of double resonance experiments on high levels in in dium served as an example to demonstrate the remarkably good agreement between theory and experiment.The use of ther mionic diodes in experiments on lithium have allowed the determination of ground state isotope shifts, which had not been detected in Rydberg D-states.The possibi lity of using sensitive Rydberg-spectroscopy for the detection of infrared photons was discussed.Another interesting subject was trapped-ion spectroscopy.Very high precision experiments in different laborato ries on hyperfine splittings have successful ly demonstrated ion cooling, which was discussed in detail at the school.This ses sion was completed by a lecture about X-ray polarisation in atomic collisions.(3) The third session covered reactive colli sions including the basis and recent results in chemiluminescence, chemical lasers, in vestigations of collisional energy transfer in vibrationally excited molecules, reactive formation of molecules in collisions and molecular beam scattering from solid sur faces.

Europhysics news•Jan 1, 1982•0 citations

Collisions and half-collisions with lasers

N. K. Rahman, Carla Guidotti

Merging two subfields, collisions and spectroscopy, this book presents the latest research proposals, innovative experiments and fresh ideas. Topics considered include radiative collision induced electron continuum-continuum scattering; models of laser-induced chemical reactions; experimental studies of laser-induced ionizing collisions; laser photodissociation of Na/sub 2/ + ions produced by laser resonant ionization of Na vapor; steady-state electron-atom collision in a laser field; conditions for the observation of the predicted splitting of the laser assisted electron impact of the differential cross section of atoms; transitions between resonances; some proposals for experiments; above-threshold multiphoton ionization; observability of optical collisions in the frequency and the time domain; laser switched collisions - a diagrammatical approach; polarization of atomic fluorescence excited by molecular photodissociation; multiphoton selective excitation; on the role of chaotic dynamics with many basins of attraction; predissociation in a strong electromagnetic field; theory of double resonance; and coherent excitation of polyatomic molecules up to highly excited vibrational states by laser light.

•Jan 1, 1984•42 citations

XXVIth International Conference on Photonic, Electronic and Atomic Collisions

Ann Orel, Anthony F. Starace, D. Nikolić +4 more

The XXVIth International Conference on Photonic, Electronic and Atomic Collisions was held on the campus of Western Michigan University (WMU) in Kalamazoo during 22–28 July 2009. Kalamazoo, the home of a major state university amid pleasant surroundings, was a delightful place for the conference. The 473 scientific participants, 111 of whom were students, had many fruitful discussions and exchanges that contributed to the success of the conference. Participants from 43 countries made the conference truly international in scope. The 590 abstracts that were presented on the first four days formed the heart of the conference and provided ample opportunity for discussion. This change, allowing the conference to end with invited talks, was a departure from the format used at previous ICPEAC gatherings in which the conferences ended with a poster session. The abstracts were split almost equally between the three main conference areas, i.e., photonic, electronic, and atomic collisions, and the posters were distributed across the days of the conference so that approximately equal numbers of abstracts in the different areas were scheduled for each day. Of the total number of presented abstracts, 517 of these are included in this proceedings volume, the first time that abstracts have been published by ICPEAC. There were 5 plenary lectures covering the different areas of the conference: Paul Corkum (University of Ottawa) talked on attosecond physics with atoms and molecules, Serge Haroche (Collège de France) on non-destructive photon counting, Toshiyuki Azuma (Tokyo Metropolitan University) on resonant coherent excitation of highly-charged ions in crystals, Eva Lindroth (Stockholm University) on atomic structure effects, and Alfred Müller (Justus Liebig University) on resonance phenomena in electron- and photon-ion collisions. Two speakers gave very illuminating public lectures that drew many people from the local area, as well as conference participants: Patricia Dehmer (US DOE) gave a talk on 'Facing Our Energy Challenges in a New Era of Science' and William Phillips (Nobel laureate, NIST) presented a talk on 'Time, Einstein, and the Coolest Stuff in the Universe'. These public talks, held on Thursday and Friday evenings, respectively, were very accessible to a general audience. In addition, there were 61 progress reports on ongoing current research, and 26 special reports selected from the submitted abstracts based on their relevance and importance. These talks covered the full range of the conference topics. Notably, this was the 50th anniversary of ICPEAC and a formal session was held the first day to honor the event as well as those who were instrumental in initiating the conference. Thirteen scientists, representing both those from the early days of ICPEAC as well as chairs of previous ICPEACs, were present and called to the stage, including Benjamin Bederson, Lewis Branscomb, Robert Crompton, Alexander Dalgarno, Gordon Dunn, Werner Eissner, Brian Gilbody, Edward Gerjuoy, Hartmut Hotop, Eugen Merzbacher, Eugene Rudd, Felix Smith, and Aaron Temkin. Steven Manson was the chair of the session and he introduced those present from the early days. Joachim Burgdörfer presented an overview of the history of ICPEAC. This session was followed by a special anniversary reception to honor all of the early 'ICPEACers'. Generous support for the conference was provided by IUPAP, the WMU President's office, and the National Science Foundation. The funds were sizeable, timely, and greatly appreciated, and permitted us to support a significant number of young scientists (postdocs and students) and persons from developing/disadvantaged countries. Nevertheless, the number of requests was far greater than the total support available (by about a factor of five!), and we had to turn down many financial requests. We encourage the organizers of the next ICPEAC to seek a higher level of funding for supporting young scientists and scientists from developing/disadvantaged countries. All in all, the XXVIth ICPEAC in Kalamazoo was very successful. The plenary lectures and the progress and special reports bridged the gap between the different fields of collision physics, making it possible for non-experts in a given area to gain insight into new areas. Also, included among the speakers were several young scientists, namely, postdocs and students, who brought new perspectives to their fields. The next ICPEAC will take place in Belfast in 2011, and the ones after that will be in Lanzhou in 2013 and Madrid in 2015. 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Journal of Physics Conference Series•Dec 1, 2009•2 citations

Frontiers in quantum optics

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The field of quantum optics has progressed rapidly in the last twenty five years with the advent of the laser. Over much of this period the phenomena studied could be described adequately by semiclassical treatments. Quite recently however, there has been a revival of interest in genuinely quantum mechanical effects. The Malvern Symposium of December 1985 brought together world experts for a meeting which concentrated largely on these quantum effects. The presentations in this unique meeting combine review material with the very latest results and so will be of value to students of quantum optics and measurement theory at all levels. The first articles cover the exciting topic of the generation of squeezed states of light in the laboratory, and their possible uses. Experimental success has been long sought and very recently attained. The reader will find presented the state of the art in this field. Next to lasing itself, optical bistability has been the most widely studied phenomenon in quantum optics, largely for its technological promise. However, it also provides a fundamental system to study quuantum effects. Recent theoretical studies of optical bistability with small numbers of atoms are surveyed. In such situations quantum features such as antibunching become significant, and the articles in this volume should be a guide to those venturing into this challenging area. In other articles discussions of fluctuations from other noise sources and instabilities in optical bistabilty are presented in a clear and interesting way. Perhaps the least classical state on quantum optics is that describing a single photon. Recent experiments which produce such states are reviewed. A theoretical review of the photon together with some new material is given which delves deeply into relativistic quantum field theory in order to describe the concept of weakly localised photon states. The material here is very rarely presented in the context of quantum optics. The history of the theory of the quantum fluctuations in a laser is then reviewed. An off-shoot of this theory is the study of quantum chaos in dissipative systems and recent results in this new area are given in a succeeding article. There are further stimulating articles on Rydberg atom systems and quantum electrodynamics. The volume ends with an entertaining and incisive study of quantum measurement problems, such as the Schrodinger cat papadox, using concepts and measuring devices found in quantum optics.other_titles

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An ultracold gas of bosonic 23Na39K ground-state molecules

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Ultracold bialkali polar molecules play a leading part at the frontline of quantum physics. They recently attract a lot of attention in the field of ultracold quantum chemistry, quantum many-body physics and quantum simulations. The key for their success is the rich internal level structure with rotational and vibrational degrees of freedom and their large electric dipole moments. Still, only a handful of molecular species are available at ultracold temperatures until now, although it is highly desirable to produce new molecular species to further expand the range of applications. Besides direct laser cooling methods for molecules, the assembly of heteronuclear ground-state molecules from ultracold atomic mixtures is the most promising approach for the creation of polar molecules. It includes the formation of weakly bound Feshbach molecules from the diatomic mixture and the subsequent two-photon stimulated Raman adiabatic passage (STIRAP) transfer to the rovibrational ground state. This creation strategy has been successfully demonstrated for the first time in the pioneering experiments at JILA with ultracold 40K87Rb molecules. Since then, only a few more molecular species from different alkali atoms have been created, namely 6Li23Na, 23Na40K, 23Na87Rb and 87Rb133Cs. In this thesis, I report the successful creation of a new species of ultracold polar ground-state molecules: 23Na39K. Starting from an ultracold mixture of bosonic 23Na and 39K atoms, weakly bound molecules are created. For this purpose, a Feshbach resonance in a high angular momentum scattering channel is chosen, experimentally identified and characterized. Close to this resonance the weakly bound Feshbach molecules are formed using resonant radio frequency radiation. For the two-photon ground-state transfer, a unique, highly specialized two-color laser system is designed and realized. It is used for one- and two-photon spectroscopy to identify the relevant transitions for the ground-state transfer. Based on the obtained data, a local model of the singlet-triplet mixed excited state manifolds is developed, with which the hyperfine structure and the magnetic field dependence is predicted with high accuracy. According to these findings, a suitable pathway to a single hyperfine ground state is chosen considering selection rules and experimental conditions such as laser polarization and beam alignment. To precisely determine the two-photon resonance condition for STIRAP, electromagnetically induced transparency measurements are performed. The ground-state transfer is then performed using STIRAP. The experimental findings regarding the STIRAP are successfully supported theoretically by a model based on a five-level master equation. The pure molecular gas shows evidence for two-body dominated loss mechanisms, such as sticky four-body collisions. The molecule-atom mixture of 23Na39K+39K reveals an unexpectedly low loss rate coefficient although sticky three-body collisions are assumed to occur. This behavior demands further investigations regarding different hyperfine collisional chan-nels and magnetic field regions.

•Jan 1, 2020•6 citations
The Summer School on Quantum Optics, the last of which was organized by J. Held, J. Czub and M. Gil of the Universi ty of Gdansk, at Cetniewo, Poland from 1-8 September 1981 has become a traditional event for young physicists from eastern and western European countries to discuss recent developments in their fields and to keep in contact.At Cetniewo, about 80 students and scientists from seven coun tries met at the well-appointed sports train ing centre on the Baltic sea.Three main subjects had been chosen and there were presented by lectures at sessions covering respectively experimental and theoretical aspects.(1) The quantum theory of electromagnetic fields and their interaction with atoms and molecules were highlighted in a series of lectures which included light-induced collisional energy transfer and changes in ato mic eigenstates by off-resonant monochro matic light.It was shown, that the emis sion spectrum of a resonant-excited two level system contains sidebands at the atomic Rabi-frequency of the laser field.Coherence and saturation phenomena in photoionisation and different aspects of optical bistability were also treated.(2) Recent experimental developments in quantum optics and atomic physics gave special emphasis to the spectroscopy of Rydberg atoms.New results of double resonance experiments on high levels in in dium served as an example to demonstrate the remarkably good agreement between theory and experiment.The use of ther mionic diodes in experiments on lithium have allowed the determination of ground state isotope shifts, which had not been detected in Rydberg D-states.The possibi lity of using sensitive Rydberg-spectroscopy for the detection of infrared photons was discussed.Another interesting subject was trapped-ion spectroscopy.Very high precision experiments in different laborato ries on hyperfine splittings have successful ly demonstrated ion cooling, which was discussed in detail at the school.This ses sion was completed by a lecture about X-ray polarisation in atomic collisions.(3) The third session covered reactive colli sions including the basis and recent results in chemiluminescence, chemical lasers, in vestigations of collisional energy transfer in vibrationally excited molecules, reactive formation of molecules in collisions and molecular beam scattering from solid sur faces.
C o m p o u n d s The Summer School on Quantum Optics, the last of which was organized by J. Held, J. Czub and M. Gil of the Universi ty of Gdansk, at Cetniewo, Poland from 1-8 September 1981 has become a traditional event for young physicists from eastern and western European countries to discuss recent developments in their fields and to keep in contact.At Cetniewo, about 80 students and scientists from seven coun tries met at the well-appointed sports train ing centre on the Baltic sea.Three main subjects had been chosen and there were presented by lectures at sessions covering respectively experimental and theoretical aspects.(1) The quantum theory of electromagnetic fields and their interaction with atoms and molecules were highlighted in a series of lectures which included light-induced collisional energy transfer and changes in ato mic eigenstates by off-resonant monochro matic light.It was shown, that the emis sion spectrum of a resonant-excited two level system contains sidebands at the atomic Rabi-frequency of the laser field.Coherence and saturation phenomena in photoionisation and different aspects of optical bistability were also treated.(2) Recent experimental developments in quantum optics and atomic physics gave special emphasis to the spectroscopy of Rydberg atoms.New results of double resonance experiments on high levels in in dium served as an example to demonstrate the remarkably good agreement between theory and experiment.The use of ther mionic diodes in experiments on lithium have allowed the determination of ground state isotope shifts, which had not been detected in Rydberg D-states.The possibi lity of using sensitive Rydberg-spectroscopy for the detection of infrared photons was discussed.Another interesting subject was trapped-ion spectroscopy.Very high precision experiments in different laborato ries on hyperfine splittings have successful ly demonstrated ion cooling, which was discussed in detail at the school.This ses sion was completed by a lecture about X-ray polarisation in atomic collisions.(3) The third session covered reactive colli sions including the basis and recent results in chemiluminescence, chemical lasers, in vestigations of collisional energy transfer in vibrationally excited molecules, reactive formation of molecules in collisions and molecular beam scattering from solid sur faces.
Merging two subfields, collisions and spectroscopy, this book presents the latest research proposals, innovative experiments and fresh ideas. Topics considered include radiative collision induced electron continuum-continuum scattering; models of laser-induced chemical reactions; experimental studies of laser-induced ionizing collisions; laser photodissociation of Na/sub 2/ + ions produced by laser resonant ionization of Na vapor; steady-state electron-atom collision in a laser field; conditions for the observation of the predicted splitting of the laser assisted electron impact of the differential cross section of atoms; transitions between resonances; some proposals for experiments; above-threshold multiphoton ionization; observability of optical collisions in the frequency and the time domain; laser switched collisions - a diagrammatical approach; polarization of atomic fluorescence excited by molecular photodissociation; multiphoton selective excitation; on the role of chaotic dynamics with many basins of attraction; predissociation in a strong electromagnetic field; theory of double resonance; and coherent excitation of polyatomic molecules up to highly excited vibrational states by laser light.
The XXVIth International Conference on Photonic, Electronic and Atomic Collisions was held on the campus of Western Michigan University (WMU) in Kalamazoo during 22–28 July 2009. Kalamazoo, the home of a major state university amid pleasant surroundings, was a delightful place for the conference. The 473 scientific participants, 111 of whom were students, had many fruitful discussions and exchanges that contributed to the success of the conference. Participants from 43 countries made the conference truly international in scope. The 590 abstracts that were presented on the first four days formed the heart of the conference and provided ample opportunity for discussion. This change, allowing the conference to end with invited talks, was a departure from the format used at previous ICPEAC gatherings in which the conferences ended with a poster session. The abstracts were split almost equally between the three main conference areas, i.e., photonic, electronic, and atomic collisions, and the posters were distributed across the days of the conference so that approximately equal numbers of abstracts in the different areas were scheduled for each day. Of the total number of presented abstracts, 517 of these are included in this proceedings volume, the first time that abstracts have been published by ICPEAC. There were 5 plenary lectures covering the different areas of the conference: Paul Corkum (University of Ottawa) talked on attosecond physics with atoms and molecules, Serge Haroche (Collège de France) on non-destructive photon counting, Toshiyuki Azuma (Tokyo Metropolitan University) on resonant coherent excitation of highly-charged ions in crystals, Eva Lindroth (Stockholm University) on atomic structure effects, and Alfred Müller (Justus Liebig University) on resonance phenomena in electron- and photon-ion collisions. Two speakers gave very illuminating public lectures that drew many people from the local area, as well as conference participants: Patricia Dehmer (US DOE) gave a talk on 'Facing Our Energy Challenges in a New Era of Science' and William Phillips (Nobel laureate, NIST) presented a talk on 'Time, Einstein, and the Coolest Stuff in the Universe'. These public talks, held on Thursday and Friday evenings, respectively, were very accessible to a general audience. In addition, there were 61 progress reports on ongoing current research, and 26 special reports selected from the submitted abstracts based on their relevance and importance. These talks covered the full range of the conference topics. Notably, this was the 50th anniversary of ICPEAC and a formal session was held the first day to honor the event as well as those who were instrumental in initiating the conference. Thirteen scientists, representing both those from the early days of ICPEAC as well as chairs of previous ICPEACs, were present and called to the stage, including Benjamin Bederson, Lewis Branscomb, Robert Crompton, Alexander Dalgarno, Gordon Dunn, Werner Eissner, Brian Gilbody, Edward Gerjuoy, Hartmut Hotop, Eugen Merzbacher, Eugene Rudd, Felix Smith, and Aaron Temkin. Steven Manson was the chair of the session and he introduced those present from the early days. Joachim Burgdörfer presented an overview of the history of ICPEAC. This session was followed by a special anniversary reception to honor all of the early 'ICPEACers'. Generous support for the conference was provided by IUPAP, the WMU President's office, and the National Science Foundation. The funds were sizeable, timely, and greatly appreciated, and permitted us to support a significant number of young scientists (postdocs and students) and persons from developing/disadvantaged countries. Nevertheless, the number of requests was far greater than the total support available (by about a factor of five!), and we had to turn down many financial requests. We encourage the organizers of the next ICPEAC to seek a higher level of funding for supporting young scientists and scientists from developing/disadvantaged countries. All in all, the XXVIth ICPEAC in Kalamazoo was very successful. The plenary lectures and the progress and special reports bridged the gap between the different fields of collision physics, making it possible for non-experts in a given area to gain insight into new areas. Also, included among the speakers were several young scientists, namely, postdocs and students, who brought new perspectives to their fields. The next ICPEAC will take place in Belfast in 2011, and the ones after that will be in Lanzhou in 2013 and Madrid in 2015. Given the rapidity with which science is advancing in all of the areas covered by ICPEAC, we expect that these future ICPEAC conferences will be as stimulating as this most recent one was, as indicated by the contributions presented in this proceedings volume. Ann Orel, University of California-Davis Anthony F Starace, University of Nebraska-Lincoln Dragan Nikolić, Western Michigan University Nora Berrah, Western Michigan University Thomas W Gorczyca, Western Michigan University Emanuel Y Kamber, Western Michigan University John A Tanis, Western Michigan University The PDF file contains details of the Sponsors and Exhibitors, Committees and Previous Proceedings.
The field of quantum optics has progressed rapidly in the last twenty five years with the advent of the laser. Over much of this period the phenomena studied could be described adequately by semiclassical treatments. Quite recently however, there has been a revival of interest in genuinely quantum mechanical effects. The Malvern Symposium of December 1985 brought together world experts for a meeting which concentrated largely on these quantum effects. The presentations in this unique meeting combine review material with the very latest results and so will be of value to students of quantum optics and measurement theory at all levels. The first articles cover the exciting topic of the generation of squeezed states of light in the laboratory, and their possible uses. Experimental success has been long sought and very recently attained. The reader will find presented the state of the art in this field. Next to lasing itself, optical bistability has been the most widely studied phenomenon in quantum optics, largely for its technological promise. However, it also provides a fundamental system to study quuantum effects. Recent theoretical studies of optical bistability with small numbers of atoms are surveyed. In such situations quantum features such as antibunching become significant, and the articles in this volume should be a guide to those venturing into this challenging area. In other articles discussions of fluctuations from other noise sources and instabilities in optical bistabilty are presented in a clear and interesting way. Perhaps the least classical state on quantum optics is that describing a single photon. Recent experiments which produce such states are reviewed. A theoretical review of the photon together with some new material is given which delves deeply into relativistic quantum field theory in order to describe the concept of weakly localised photon states. The material here is very rarely presented in the context of quantum optics. The history of the theory of the quantum fluctuations in a laser is then reviewed. An off-shoot of this theory is the study of quantum chaos in dissipative systems and recent results in this new area are given in a succeeding article. There are further stimulating articles on Rydberg atom systems and quantum electrodynamics. The volume ends with an entertaining and incisive study of quantum measurement problems, such as the Schrodinger cat papadox, using concepts and measuring devices found in quantum optics.other_titles
Ultracold bialkali polar molecules play a leading part at the frontline of quantum physics. They recently attract a lot of attention in the field of ultracold quantum chemistry, quantum many-body physics and quantum simulations. The key for their success is the rich internal level structure with rotational and vibrational degrees of freedom and their large electric dipole moments. Still, only a handful of molecular species are available at ultracold temperatures until now, although it is highly desirable to produce new molecular species to further expand the range of applications. Besides direct laser cooling methods for molecules, the assembly of heteronuclear ground-state molecules from ultracold atomic mixtures is the most promising approach for the creation of polar molecules. It includes the formation of weakly bound Feshbach molecules from the diatomic mixture and the subsequent two-photon stimulated Raman adiabatic passage (STIRAP) transfer to the rovibrational ground state. This creation strategy has been successfully demonstrated for the first time in the pioneering experiments at JILA with ultracold 40K87Rb molecules. Since then, only a few more molecular species from different alkali atoms have been created, namely 6Li23Na, 23Na40K, 23Na87Rb and 87Rb133Cs. In this thesis, I report the successful creation of a new species of ultracold polar ground-state molecules: 23Na39K. Starting from an ultracold mixture of bosonic 23Na and 39K atoms, weakly bound molecules are created. For this purpose, a Feshbach resonance in a high angular momentum scattering channel is chosen, experimentally identified and characterized. Close to this resonance the weakly bound Feshbach molecules are formed using resonant radio frequency radiation. For the two-photon ground-state transfer, a unique, highly specialized two-color laser system is designed and realized. It is used for one- and two-photon spectroscopy to identify the relevant transitions for the ground-state transfer. Based on the obtained data, a local model of the singlet-triplet mixed excited state manifolds is developed, with which the hyperfine structure and the magnetic field dependence is predicted with high accuracy. According to these findings, a suitable pathway to a single hyperfine ground state is chosen considering selection rules and experimental conditions such as laser polarization and beam alignment. To precisely determine the two-photon resonance condition for STIRAP, electromagnetically induced transparency measurements are performed. The ground-state transfer is then performed using STIRAP. The experimental findings regarding the STIRAP are successfully supported theoretically by a model based on a five-level master equation. The pure molecular gas shows evidence for two-body dominated loss mechanisms, such as sticky four-body collisions. The molecule-atom mixture of 23Na39K+39K reveals an unexpectedly low loss rate coefficient although sticky three-body collisions are assumed to occur. This behavior demands further investigations regarding different hyperfine collisional chan-nels and magnetic field regions.