Editorial: Quo vadis, cold molecules? (original) (raw)
Related papers
Cold and ultracold molecules: science, technology and applications
New Journal of Physics, 2009
This article presents a review of the current state of the art in the research field of cold and ultracold molecules. It serves as an introduction to the Special Issue of the New Journal of Physics on Cold and Ultracold Molecules and describes new prospects for fundamental research and technological development. Cold and ultracold molecules may revolutionize physical chemistry and few body physics, provide techniques for probing new states of quantum matter, allow for precision measurements of both fundamental and applied interest, and enable quantum simulations of condensed-matter phenomena. Ultracold molecules offer promising applications such as new platforms for quantum computing, precise control of molecular dynamics, nanolithography, and Bose-enhanced chemistry. The discussion is based on recent experimental and theoretical work and concludes with a summary of anticipated future directions and open questions in this rapidly expanding research field.
An experimental toolbox for the generation of cold and ultracold polar molecules
Journal of Physics: Conference Series, 2017
Progress toward ultracold chemistry: ultracold atomic and photonic collisions Jesús Pérez-Ríos, Maxence Lepers, Romain Vexiau et al. Thermodynamic of mixtures of ultracold Rydberg gases with different levels of excitation B V Zelener, S Y Bronin and A B Klyarfeld Nondestructive detection of polar molecules via Rydberg atoms M. Zeppenfeld Production and Detection of Ultracold Ground State 85Rb133Cs Molecules in the Lowest Vibrational Level by Short-Range Photoassociation
Quantum optics of ultra-cold molecules
2005
Quantum optics has been a major driving force behind the rapid experimental developments that have led from the first laser cooling schemes to the Bose-Einstein condensation (BEC) of dilute atomic and molecular gases. Not only has it provided experimentalists with the necessary tools to create ultra-cold atomic systems, but it has also provided theorists with a formalism and framework to describe them: many effects now being studied in quantum-degenerate atomic and molecular systems find a very natural explanation in a quantum optics picture. This article briefly reviews three such examples that find their direct inspiration in the trailblazing work carried out over the years by Herbert Walther, one of the true giants of that field. Specifically, we use an analogy with the micromaser to analyze ultra-cold molecules in a double-well potential; study the formation and dissociation dynamics of molecules using the passage time statistics familiar from superradiance and superfluorescence studies; and show how molecules can be used to probe higher-order correlations in ultra-cold atomic gases, in particular bunching and antibunching.
Optoelectrical cooling of polar molecules
Physical Review A, 2009
We present an opto-electrical cooling scheme for polar molecules based on a Sisyphus-type cooling cycle in suitably tailored electric trapping fields. Dissipation is provided by spontaneous vibrational decay in a closed level scheme found in symmetric-top rotors comprising six low-field-seeking rovibrational states. A generic trap design is presented. Suitable molecules are identified with vibrational decay rates on the order of 100 Hz. A simulation of the cooling process shows that the molecular temperature can be reduced from 1 K to 1 mK in approximately 10 s. The molecules remain electrically trapped during this time, indicating that the ultracold regime can be reached in an experimentally feasible scheme.
Ultracold molecules and ultracold chemistry
Molecular Physics, 2009
The recent development of a range of new methods for producing samples of gas phase molecules that are translationally cold (T ≤ 1 K) or ultracold (T ≤ 1 mK) is driving efforts to study reactive and inelastic collisional processes in these temperature regimes. In this review article the new methods for cold/ultracold molecule production are reviewed in the context of their potential or current use in collisional studies and progress in the application of these methods is highlighted. In these sub-Kelvin temperature ranges, where the de Broglie wavelength is long compared to molecular dimensions, quantum effects may play a crucial role in the collision dynamics. Reactions with no potential energy barrier are of greatest importance, and this review article summarises some of the principal theoretical approaches to understanding quantum effects in these barrierless processes.
Physica Scripta, 2004
The quantum physics of light is a most fascinating field. Here I present a very personal viewpoint, focusing on my own path to quantum entanglement and then on to applications. I have been fascinated by quantum physics ever since I heard about it for the first time in school. The theory struck me immediately for two reasons: (1) its immense mathematical beauty, and (2) the unparalleled precision to which its predictions have been verified again and again. Particularly fascinating for me were the predictions of quantum mechanics for individual particles, individual quantum systems. Surprisingly, the experimental realization of many of these fundamental phenomena has led to novel ideas for applications. Starting from my early experiments with neutrons, I later became interested in quantum entanglement, initially focusing on multi-particle entanglement like GHZ states. This work opened the experimental possibility to do quantum teleportation and quantum hyper-dense coding. The latter became the first entanglement-based quantum experiment breaking a classical limitation. One of the most fascinating phenomena is entanglement swapping, the teleportation of an entangled state. This phenomenon is fundamentally interesting because it can entangle two pairs of particles which do not share any common past. Surprisingly, it also became an important ingredient in a number of applications, including quantum repeaters which will connect future quantum computers with each other. Another application is entanglement-based quantum cryptography where I present some recent long-distance experiments. Entanglement swapping has also been applied in very recent so-called loophole-free tests of Bell's theorem. Within the physics community such loophole-free experiments are perceived as providing nearly definitive proof that local realism is untenable. While, out of principle, local realism can never be excluded entirely, the 2015 achievements narrow down the remaining possibilities for local realistic explanations of the quantum phenomenon of entanglement in a significant way. These experiments may go down in the history books of science. Future experiments will address particularly the freedom-of-choice loophole using cosmic sources of randomness. Such experiments confirm that unconditionally secure quantum cryptography is possible, since quantum cryptography based on Bell's theorem can provide unconditional security. The fact that the experiments were loophole-free proves that an eavesdropper cannot avoid detection in an experiment that correctly follows the protocol. I finally discuss some recent experiments with single-and entangled-photon states in higher dimensions. Such experiments realized quantum entanglement between two photons, each with quantum numbers beyond 10 000 and also simultaneous entanglement of two photons where each carries more than 100 dimensions. Thus they offer the possibility of quantum communication with more than one bit or qubit per photon. The paper concludes discussing Einstein's contributions and viewpoints of quantum mechanics. Even if some of his positions are not supported by recent experiments, he has to be given credit for the fact that his analysis of fundamental issues gave rise to developments which led to a new information technology. Finally, I reflect on some of the lessons learned by the fact that Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
Ultracold polyatomic molecules for quantum science and precision measurements
2022
Polar molecules, due to their intrinsic electric dipole moment and their controllable complexity, are a powerful platform for precision measurement searches for physics beyond the Standard Model (BSM) and for quantum simulation/computation. This has led to many experimental efforts to cool and control molecules at the quantum level. Due to their qualitatively unique rotational and vibrational modes, polyatomic molecules (molecules containing three or more atoms) have attracted recent focus as quantum resources that have distinct advantages and challenges compared to both atoms and diatomic molecules. Here we discuss results on the laser cooling of polyatomic molecules into the ultracold regime and future prospects for the use of polyatomic molecules to greatly improve fundamental symmetry tests, searches for dark matter, and the search for CP-violating BSM physics.
Ultracold polar molecules near quantum degeneracy
Faraday Discussions, 2009
We report the creation and characterization of a near quantum-degenerate gas of polar 40 K-87 Rb molecules in their absolute rovibrational ground state. Starting from weakly bound heteronuclear KRb Feshbach molecules, we implement precise control of the molecular electronic, vibrational, and rotational degrees of freedom with phase-coherent laser fields. In particular, we coherently transfer these weakly bound molecules across a 125 THz frequency gap in a single step into the absolute rovibrational ground state of the electronic ground potential. Phase coherence between lasers involved in the transfer process is ensured by referencing the lasers to two single components of a phase-stabilized optical frequency comb. Using these methods, we prepare a dense gas of 4 · 10 4 polar molecules at a temperature below 400 nK. This fermionic molecular ensemble is close to quantum degeneracy and can be characterized by a degeneracy parameter of T /TF = 3. We have measured the molecular polarizability in an optical dipole trap where the trap lifetime gives clues to interesting ultracold chemical processes. Given the large measured dipole moment of the KRb molecules of 0.5 Debye, the study of quantum degenerate molecular gases interacting via strong dipolar interactions is now within experimental reach.
Quantum encounters of the cold kind
2002
NATURE | VOL 416 | 14 MARCH 2002 | www.nature.com 225 T he behaviour of atoms and their interactions at ultracold temperatures is a fascinating area of study. These interactions and their effects distinguish them from those encountered in collisions at room temperature. The realization that these interactions would be both subtle and interesting began in the 1970s with studies 1 of spinpolarized hydrogen and long-range molecules, and expanded as laser cooling 2-4 reached temperatures in the millikelvin and then microkelvin ranges . With the advent of evaporative cooling 5 and the production of atomic Bose-Einstein condensates (BECs; see ref. 6 and the review in this issue by Anglin and Ketterle, pages 211-218), we now require a detailed understanding of atomic interactions at nanokelvin temperatures. These applications have driven a tremendous growth of interest in the field.
Cold molecules: Progress in quantum engineering of chemistry and quantum matter
Science (New York, N.Y.), 2017
Cooling atoms to ultralow temperatures has produced a wealth of opportunities in fundamental physics, precision metrology, and quantum science. The more recent application of sophisticated cooling techniques to molecules, which has been more challenging to implement owing to the complexity of molecular structures, has now opened the door to the longstanding goal of precisely controlling molecular internal and external degrees of freedom and the resulting interaction processes. This line of research can leverage fundamental insights into how molecules interact and evolve to enable the control of reaction chemistry and the design and realization of a range of advanced quantum materials.