Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)

From micromasers to microlasers

HERBERT WALTHER

Published Jan 1, 1994• 0 citations
Publisher

Abstract

The one-atom maser or micromaser is, in contrary to ordinary masers and lasers, a pure quantum device operating with only a few photons and less than one pump atom on the average in the maser cavity. It is thus an ideal device to study quantum phenomena such as the generation of nonclassical light. The cavity is a superconducting niobium microwave resonator with a high quality factor (up to 3 × 1010). Using a single trapped ion related experiments can now also be performed in the infrared spectral region.

DOI
10.1364/cleo_europe.1994.pl1

Related papers

From micromaser to microlasers

HERBERT WALTHER

In this paper the work on the one-atom-maser or micromaser is reviewed. This maser system is the most fundamental one where a single atom interacts with a single mode of a cavity. With this setup the generation process of non-classical light and other quantum phenomena can be investigated in detail. Furthermore a brief review of the microlaser work will be given where the phenomena of cavity quantum electrodynamics lead to a very low threshold of the laser system.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Mar 8, 1995•0 citations

Theory of the micromaser

Marlan O. Scully, Muhammad Suhail Zubairy

The development of a single-atom maser or a micromaser allows a detailed study of the atom–field interaction. The situation realized is very close to the ideal case of a single two-level atom interacting with a single-mode quantized field as treated in Section 6.2. In a micromaser a stream of two-level atoms is injected into a superconducting cavity with a high quality factor. The injection rate can be such that only one atom is present inside the resonator at any time. Due to the high quality factor of the cavity, the radiation decay time is much larger than the characteristic time of the atom–field interaction, which is given by the inverse of the single-photon Rabi frequency. Therefore, a field is built up inside the cavity when the mean time between the atoms injected into the cavity is shorter than the cavity decay time. A micromaser, therefore, allows sustained oscillations with less than one atom on the average in the cavity. The realization of a single-atom maser or a micromaser has been made possible due to the enormous progress in the construction of superconducting cavities together with the laser preparation of highly excited atoms called Rydberg atoms. The quality factor of the superconducting cavities is high enough for periodic energy exchanges between atom and cavity field to be observed. The interesting properties of the Rydberg atoms make them ideal for micromasers. In Rydberg atoms the probability of induced transitions between adjacent states becomes very large and scales as n 4 , where n denotes the principle quantum number.

Cambridge University Press eBooks•Sep 4, 1997•1 citation

Single-atom experiments and the test of fundamental quantum physics

HERBERT WALTHER

The work on the one-atom maser is reviewed. The superconducting maser cavity made of niobium and cooled to 0.5 K to exclude thermal photons has a quality factor of 3 X 1010. Velocity-selected Rydberg atoms pump the maser. The field inside the cavity is investigated by probing the atoms leaving the cavity. The dynamics of the Rabi nutation were investigated. Furthermore, the statistics of the photons in the cavity were determined to be sub-Poissonian corresponding to photon-number fluctuations of 70% below the vacuum-state limit. The one-atom maser is the only maser system which leads to nonclassical radiation even when pumping processes with Poissonian statistics are used. Some applications of the one- atom maser to study the quantum measurement process also are discussed.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Oct 28, 1992•0 citations

The Jaynes–Cummings Model and the One-Atom-Maser

HERBERT WALTHER

. In this paper experiments performed with the one-atom maser are reviewed. Furthermore, possible experiments to test basic quantum physics are discussed. Introduction, the One-Atom-Maser The most promising avenue to study the generation process of radiation in lasers and masers is to drive a maser consisting of a single mode cavity by single atoms. This system, at first glance, seems to be another example of a Gedanken-experiment treated in the pioneering work of Jaynes and Cummings (1963), but such a one-atom maser (Meschede, Walther and Müller, 1985) really exists and can in addition be used to study the basic principles of radiation-atom interaction. The advantages of the system are: it is the first maser which sustains oscillations with less than one atom on the average in the cavity, this setup allows to study in detail the conditions necessary to obtain nonclassical radiation, especially radiation with sub-Poissonian photon statistics in a maser system directly in a Poissonian pumping process, and it is possible to study a variety of phenomena of a quantum field including the quantum measurement process. What are the tools that make this device work: It was the enormous progress in constructing superconducting cavities together with the laser preparation of highly excited atoms – Rydberg atoms – that have made the realization of such a one-atom maser possible.

Cambridge University Press eBooks•Sep 2, 1993•1 citation

Construction, Theory and simulation of Cavity QED Systems

Mark S. Everitt

The microscopically pumped maser, or micromaser is a cavity QED experiment intended to be a physical realisation of the Jaynes-Cummings model of a single two-level atom interacting with a single mode electromagnetic field. This is the simplest model that describes the interaction between light and matter, yet it predicts behaviour unexpected from semiclassical models, such as the revival of Rabi oscillations of an atom interacting with an initially coherent field and non-monotonic linewidth as a function of pumping. The micromaser at the University of Leeds consists of a high quality superconducting microwave cavity designed to be resonant with the transition between two specific Rydberg states of rubidium. These two states behave like an ideal two level atom, and couple strongly to the cavity field due to a large dipole moment. These Rydberg atoms are passed through the cavity in a rarified beam such that in most instances when there is an atom in the cavity, there will only be one, closely approximating the Jaynes-Cummings model. I present experimental work on the build phase of the micromaser. Specifically I routed all of the wiring and microwave lines in the cryostat that contains the micromaser, and designed mounts for various components. I also designed several testing methods for probing high quality microwave cavity resonances and quality factors which are presented. Using the Jaynes-Cummings model as a prototype, I demonstrate how extensions to the model can be used to construct universal quantum logic gates that operate on photonic qubits in a multi-mode cavity. This could be realised in a micromaser with a multi-mode cavity. Conversely, I demonstrate that by using atoms as qubits, detuned cavities can be used to generate entangled resources such as the Greenberger-Horne-Zeilinger state, the W state, and graph states of atoms. I show that single qubit rotations on Rydberg atom qubits have already been experimentally demonstrated so that in combination these entangled resources are useful for quantum metrology, quantum computation and even tests of quantum gravity.

•Sep 1, 2009•0 citations

The One-Atom Maser and the Generation of Nonclassical Light

Gerhard Rempe, Marlan O. Scully, HERBERT WALTHER

We review our recent work on the nonclassical radiation field of a one-atom maser. The maser cavity is cooled to 0.5 K to exclude thermal photons and has a quality factor of 3 × 10 10 . Velocity-selected Rydberg atoms pump the maser. The field inside the cavity is measured via the fluctuations in the number of atoms leaving the cavity in the lower maser level which are up to 40% below the Poisson level. This corresponds to photon-number fluctuations 70% below the vacuum-state limit. The one-atom maser is the only maser system which leads to nonclassical radiation even when pumping processes with Poissonian statistics are used. We analyse and propose new experiments based on the one-atom maser leading to new studies of the quantum measurement process.

Physica Scripta•Jan 1, 1991•25 citations
The one-atom maser or micromaser is, in contrary to ordinary masers and lasers, a pure quantum device operating with only a few photons and less than one pump atom on the average in the maser cavity. It is thus an ideal device to study quantum phenomena such as the generation of nonclassical light. The cavity is a superconducting niobium microwave resonator with a high quality factor (up to 3 × 1010). Using a single trapped ion related experiments can now also be performed in the infrared spectral region.
The development of a single-atom maser or a micromaser allows a detailed study of the atom–field interaction. The situation realized is very close to the ideal case of a single two-level atom interacting with a single-mode quantized field as treated in Section 6.2. In a micromaser a stream of two-level atoms is injected into a superconducting cavity with a high quality factor. The injection rate can be such that only one atom is present inside the resonator at any time. Due to the high quality factor of the cavity, the radiation decay time is much larger than the characteristic time of the atom–field interaction, which is given by the inverse of the single-photon Rabi frequency. Therefore, a field is built up inside the cavity when the mean time between the atoms injected into the cavity is shorter than the cavity decay time. A micromaser, therefore, allows sustained oscillations with less than one atom on the average in the cavity. The realization of a single-atom maser or a micromaser has been made possible due to the enormous progress in the construction of superconducting cavities together with the laser preparation of highly excited atoms called Rydberg atoms. The quality factor of the superconducting cavities is high enough for periodic energy exchanges between atom and cavity field to be observed. The interesting properties of the Rydberg atoms make them ideal for micromasers. In Rydberg atoms the probability of induced transitions between adjacent states becomes very large and scales as n 4 , where n denotes the principle quantum number.
The work on the one-atom maser is reviewed. The superconducting maser cavity made of niobium and cooled to 0.5 K to exclude thermal photons has a quality factor of 3 X 1010. Velocity-selected Rydberg atoms pump the maser. The field inside the cavity is investigated by probing the atoms leaving the cavity. The dynamics of the Rabi nutation were investigated. Furthermore, the statistics of the photons in the cavity were determined to be sub-Poissonian corresponding to photon-number fluctuations of 70% below the vacuum-state limit. The one-atom maser is the only maser system which leads to nonclassical radiation even when pumping processes with Poissonian statistics are used. Some applications of the one- atom maser to study the quantum measurement process also are discussed.
. In this paper experiments performed with the one-atom maser are reviewed. Furthermore, possible experiments to test basic quantum physics are discussed. Introduction, the One-Atom-Maser The most promising avenue to study the generation process of radiation in lasers and masers is to drive a maser consisting of a single mode cavity by single atoms. This system, at first glance, seems to be another example of a Gedanken-experiment treated in the pioneering work of Jaynes and Cummings (1963), but such a one-atom maser (Meschede, Walther and Müller, 1985) really exists and can in addition be used to study the basic principles of radiation-atom interaction. The advantages of the system are: it is the first maser which sustains oscillations with less than one atom on the average in the cavity, this setup allows to study in detail the conditions necessary to obtain nonclassical radiation, especially radiation with sub-Poissonian photon statistics in a maser system directly in a Poissonian pumping process, and it is possible to study a variety of phenomena of a quantum field including the quantum measurement process. What are the tools that make this device work: It was the enormous progress in constructing superconducting cavities together with the laser preparation of highly excited atoms – Rydberg atoms – that have made the realization of such a one-atom maser possible.
The microscopically pumped maser, or micromaser is a cavity QED experiment intended to be a physical realisation of the Jaynes-Cummings model of a single two-level atom interacting with a single mode electromagnetic field. This is the simplest model that describes the interaction between light and matter, yet it predicts behaviour unexpected from semiclassical models, such as the revival of Rabi oscillations of an atom interacting with an initially coherent field and non-monotonic linewidth as a function of pumping. The micromaser at the University of Leeds consists of a high quality superconducting microwave cavity designed to be resonant with the transition between two specific Rydberg states of rubidium. These two states behave like an ideal two level atom, and couple strongly to the cavity field due to a large dipole moment. These Rydberg atoms are passed through the cavity in a rarified beam such that in most instances when there is an atom in the cavity, there will only be one, closely approximating the Jaynes-Cummings model. I present experimental work on the build phase of the micromaser. Specifically I routed all of the wiring and microwave lines in the cryostat that contains the micromaser, and designed mounts for various components. I also designed several testing methods for probing high quality microwave cavity resonances and quality factors which are presented. Using the Jaynes-Cummings model as a prototype, I demonstrate how extensions to the model can be used to construct universal quantum logic gates that operate on photonic qubits in a multi-mode cavity. This could be realised in a micromaser with a multi-mode cavity. Conversely, I demonstrate that by using atoms as qubits, detuned cavities can be used to generate entangled resources such as the Greenberger-Horne-Zeilinger state, the W state, and graph states of atoms. I show that single qubit rotations on Rydberg atom qubits have already been experimentally demonstrated so that in combination these entangled resources are useful for quantum metrology, quantum computation and even tests of quantum gravity.
We review our recent work on the nonclassical radiation field of a one-atom maser. The maser cavity is cooled to 0.5 K to exclude thermal photons and has a quality factor of 3 × 10 10 . Velocity-selected Rydberg atoms pump the maser. The field inside the cavity is measured via the fluctuations in the number of atoms leaving the cavity in the lower maser level which are up to 40% below the Poisson level. This corresponds to photon-number fluctuations 70% below the vacuum-state limit. The one-atom maser is the only maser system which leads to nonclassical radiation even when pumping processes with Poissonian statistics are used. We analyse and propose new experiments based on the one-atom maser leading to new studies of the quantum measurement process.