© 2026 Aqora Quantum S.A.S.

Terms Privacy Legal Notice

Journal of Cluster Science

A Condensed Excited (Rydberg) Matter: Perspective and Applications

Tor Håvard Aasen, Dag Herman Zeiner‐Gundersen, Sindre Zeiner-Gundersen, Per Alfred Øhlckers, Kaiying Wang

Published Mar 5, 2021• 6 citations

Abstract

Abstract A condensed excited matter called Rydberg Matter (RM) have been studied experimentally for 30 years, but have not sparked widespread attention yet, unlike ordinary Rydberg atoms. RM formed by clusters of Rydberg atoms at a solid surface have a longer lifetime compared to Rydberg atoms, and is liquid-like. This review describes how the RM state is generated, and its potential applications. These include using RM for research into catalysis, space phenomena and sensor applications, or for producing environmentally friendly energy. A background on RM is presented, with its structure and special properties, and the working principle of RM generation. The experimental set-ups, materials, and detectors used are discussed, together with methods to improve the amount of RM produced. The materials used for the catalysts are of special interest, as this should have a large influence on the energy of the RM, and therefore also on the applications. Currently most of the catalysts used are potassium doped iron oxide designed for styrene production, which should give the possibility of improvements. And as there is little knowledge on the exact mechanisms for RM formation, suggestions are given as to where research should start.

DOI: 10.1007/s10876-021-02031-6

Related papers

Rydberg matter—A long-lived excited state of matter

Leif Holmlid, Edward A. Manykin

The theory of condensed excited matter, the so-called Rydberg matter (RM), is examined briefly. Explicit results are given for several physical quantities, notably, the work function and the resistivity, for which experimental results exist. The most important aspects of the experiments, which are fully described elsewhere, are discussed. Large densities of Rydberg species are formed in the experiments with cesium vapor in contact with carbon (graphite) surfaces. The resistivity of the RM formed is found to be 10 −2 –10 −3 Ω·m under varying conditions, while theory gives the order of 10 −3 Ω·m. The work function is experimentally found to be less than 0.7 eV, perhaps even less than 0.5 eV. Two different methods were used to extract this quantity from thermionic diode data. These work function values are much lower than reported for any known material, especially at the high temperatures, and they thus give strong support for the description of RM as a very dilute metal. Theory gives values ranging from 0.6 down to 0.2 eV, depending on the principal quantum number, which is estimated to be n =12–14 from the lifetime calculations and from the known pressure. Supporting evidence is found from spectroscopic studies of RM, from jellium calculations, and from recent confirming experiments. From the good agreement between theory and experiment we conclude that RM exists.

Journal of Experimental and Theoretical Physics•May 1, 1997•13 citations

Rydberg matter: properties and decay

Edward A. Manykin, Michael I. Ojovan, Pavel P. Poluektov

Rydberg matter is a condensed excited state made of highly excited atoms. State of art of research in the field of Rydberg matter is briefly reviewed. Special attention is focused on the contribution of Russian and Swedish scientists' groups to the analysis of this problem. Most attention is concentrated on physical principles of pseudopotential method and density functional theory used to describe the Rydberg matter. The description of Rydberg matter as an excited state becomes viable after the formal replacement of excited atoms by ground state pseudoatoms. This procedure has been used to find parameters of Rydberg matter made of highly excited cesium atoms. Theoretical estimations conform to experimental data available.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Mar 3, 2006•17 citations

Rydberg-state species in a strong laser field

Edward A. Manykin

A brief state-of-art review of the research into the interaction of laser radiation with Rydberg atoms and clusters of Rydberg atoms is provided. The dynamics of various Rydberg species in a high-frequency optical field is described with the use of the quantum-mechanical approach. Experimental data indicating the existence of Rydberg-state species (Rydberg clusters and Rydberg matter) are analyzed. A special emphasis is placed on Raman processes in Rydberg atoms and Rydberg matter created on solid surfaces.

Laser Physics•Jan 1, 2003•0 citations

Interaction of Rydberg atoms with surfaces

Mike Kohlhoff

The interface of neutral Rydberg atoms in the gas phase with a solid surface is of interest in many fields of modern research. This interface poses a particular challenge for any application in which Rydberg atoms are close to a substrate but also opens up the possibility of studying properties of the surface material itself through the atomic response. In this review the focus is on the process of electron tunneling from the excited state into the substrate that occurs when a Rydberg atom is located in front of a surface at a range of a few hundred nm and is demonstrated with a metallic surface. It is shown how variations in this ionisation mechanism can provide a powerful tool to probe image-charge effects, measure small superficial electric stray or patch fields and how charge transfer from the Rydberg atom can be in resonance with energetically discrete surface states.

The European Physical Journal Special Topics•Dec 1, 2016•12 citations

Adiabatic formation of Rydberg crystals with chirped laser pulses

Rick van Bijnen, Sjoerd Smit, K. A. H. van Leeuwen +2 more

Ultracold atomic gases have been used extensively in recent years to realize textbook examples of condensed matter phenomena. Recently, phase transitions to ordered structures have been predicted for gases of highly excited, 'frozen' Rydberg atoms. Such Rydberg crystals are a model for dilute metallic solids with tunable lattice parameters, and provide access to a wide variety of fundamental phenomena. We investigate theoretically how such structures can be created in four distinct cold atomic systems, by using tailored laser-excitation in the presence of strong Rydberg-Rydberg interactions. We study in detail the experimental requirements and limitations for these systems, and characterize the basic properties of small crystalline Rydberg structures in one, two and three dimensions.

arXiv:1103.2096•Journal of Physics B Atomic Molecular and Optical Physics•Sep 14, 2011•65 citations

Recent advances in Ultralong-range Rydberg molecules

Jingxu Bai, Yuechun Jiao, Xiao-Qiang Shao +2 more

Rydberg molecule, formed by one or more Rydberg atoms, exhibits remarkable properties, including an exceptionally large spatial extent, rich rovibrational level structures, permanent electric dipole moments, and a pronounced sensitivity to external fields. Based on the underlying binding mechanisms, Rydberg molecules can be divided into three categories, the ground-Rydberg molecule that is bound via a low-energy electron-atom scattering interaction between ground atom and Rydberg electron, the Rydberg-Rydberg molecule that is bound via a long-range electrostatic interaction between Rydberg atoms, and the ion-Rydberg molecule that is bound via single- or multi-polar interactions between Rydberg atom and ion. This review focuses on recent theoretical and experimental advances in diatomic Rydberg molecules, covering their formation and binding mechanisms, potential energy curves, experimental observations, and spectroscopic properties, with the aim of providing a comprehensive overview of the current state and future prospects of this rapidly developing field.

physics.atom-phCross-listedarXiv:2603.09091•Chinese Physics B•Mar 11, 2026•0 citations

Abstract A condensed excited matter called Rydberg Matter (RM) have been studied experimentally for 30 years, but have not sparked widespread attention yet, unlike ordinary Rydberg atoms. RM formed by clusters of Rydberg atoms at a solid surface have a longer lifetime compared to Rydberg atoms, and is liquid-like. This review describes how the RM state is generated, and its potential applications. These include using RM for research into catalysis, space phenomena and sensor applications, or for producing environmentally friendly energy. A background on RM is presented, with its structure and special properties, and the working principle of RM generation. The experimental set-ups, materials, and detectors used are discussed, together with methods to improve the amount of RM produced. The materials used for the catalysts are of special interest, as this should have a large influence on the energy of the RM, and therefore also on the applications. Currently most of the catalysts used are potassium doped iron oxide designed for styrene production, which should give the possibility of improvements. And as there is little knowledge on the exact mechanisms for RM formation, suggestions are given as to where research should start.

The theory of condensed excited matter, the so-called Rydberg matter (RM), is examined briefly. Explicit results are given for several physical quantities, notably, the work function and the resistivity, for which experimental results exist. The most important aspects of the experiments, which are fully described elsewhere, are discussed. Large densities of Rydberg species are formed in the experiments with cesium vapor in contact with carbon (graphite) surfaces. The resistivity of the RM formed is found to be 10 −2 –10 −3 Ω·m under varying conditions, while theory gives the order of 10 −3 Ω·m. The work function is experimentally found to be less than 0.7 eV, perhaps even less than 0.5 eV. Two different methods were used to extract this quantity from thermionic diode data. These work function values are much lower than reported for any known material, especially at the high temperatures, and they thus give strong support for the description of RM as a very dilute metal. Theory gives values ranging from 0.6 down to 0.2 eV, depending on the principal quantum number, which is estimated to be n =12–14 from the lifetime calculations and from the known pressure. Supporting evidence is found from spectroscopic studies of RM, from jellium calculations, and from recent confirming experiments. From the good agreement between theory and experiment we conclude that RM exists.

Rydberg matter is a condensed excited state made of highly excited atoms. State of art of research in the field of Rydberg matter is briefly reviewed. Special attention is focused on the contribution of Russian and Swedish scientists' groups to the analysis of this problem. Most attention is concentrated on physical principles of pseudopotential method and density functional theory used to describe the Rydberg matter. The description of Rydberg matter as an excited state becomes viable after the formal replacement of excited atoms by ground state pseudoatoms. This procedure has been used to find parameters of Rydberg matter made of highly excited cesium atoms. Theoretical estimations conform to experimental data available.

A brief state-of-art review of the research into the interaction of laser radiation with Rydberg atoms and clusters of Rydberg atoms is provided. The dynamics of various Rydberg species in a high-frequency optical field is described with the use of the quantum-mechanical approach. Experimental data indicating the existence of Rydberg-state species (Rydberg clusters and Rydberg matter) are analyzed. A special emphasis is placed on Raman processes in Rydberg atoms and Rydberg matter created on solid surfaces.

The interface of neutral Rydberg atoms in the gas phase with a solid surface is of interest in many fields of modern research. This interface poses a particular challenge for any application in which Rydberg atoms are close to a substrate but also opens up the possibility of studying properties of the surface material itself through the atomic response. In this review the focus is on the process of electron tunneling from the excited state into the substrate that occurs when a Rydberg atom is located in front of a surface at a range of a few hundred nm and is demonstrated with a metallic surface. It is shown how variations in this ionisation mechanism can provide a powerful tool to probe image-charge effects, measure small superficial electric stray or patch fields and how charge transfer from the Rydberg atom can be in resonance with energetically discrete surface states.

Ultracold atomic gases have been used extensively in recent years to realize textbook examples of condensed matter phenomena. Recently, phase transitions to ordered structures have been predicted for gases of highly excited, 'frozen' Rydberg atoms. Such Rydberg crystals are a model for dilute metallic solids with tunable lattice parameters, and provide access to a wide variety of fundamental phenomena. We investigate theoretically how such structures can be created in four distinct cold atomic systems, by using tailored laser-excitation in the presence of strong Rydberg-Rydberg interactions. We study in detail the experimental requirements and limitations for these systems, and characterize the basic properties of small crystalline Rydberg structures in one, two and three dimensions.

Rydberg molecule, formed by one or more Rydberg atoms, exhibits remarkable properties, including an exceptionally large spatial extent, rich rovibrational level structures, permanent electric dipole moments, and a pronounced sensitivity to external fields. Based on the underlying binding mechanisms, Rydberg molecules can be divided into three categories, the ground-Rydberg molecule that is bound via a low-energy electron-atom scattering interaction between ground atom and Rydberg electron, the Rydberg-Rydberg molecule that is bound via a long-range electrostatic interaction between Rydberg atoms, and the ion-Rydberg molecule that is bound via single- or multi-polar interactions between Rydberg atom and ion. This review focuses on recent theoretical and experimental advances in diatomic Rydberg molecules, covering their formation and binding mechanisms, potential energy curves, experimental observations, and spectroscopic properties, with the aim of providing a comprehensive overview of the current state and future prospects of this rapidly developing field.