Ultracold collisions of oxygen molecules
نویسندگان
چکیده
Collision cross sections and rate constants between two ground-state oxygen molecules are investigated theoretically at translational energies below ;1 K and in zero magnetic field. We present calculations for elastic and spin-changing inelastic collision rates for different isotopic combinations of oxygen atoms as a prelude to understanding their collisional stability in ultracold magnetic traps. A numerical analysis has been made in the framework of a rigid-rotor model that accounts fully for the singlet, triplet, and quintet potentialenergy surfaces in this system. The results offer insights into the effectiveness of evaporative cooling and the properties of molecular Bose-Einstein condensates, as well as estimates of collisional lifetimes in magnetic traps. Specifically, O2 looks like a good candidate for ultracold studies, while O2 is unlikely to survive evaporative cooling. Since O2 is representative of a wide class of molecules that are paramagnetic in their ground state we conclude that many molecules can be successfully magnetically trapped at ultralow temperatures.
منابع مشابه
. at om - p h ] 2 3 M ay 2 00 1 Ultracold collisions of oxygen molecules
Collision cross sections and rate constants between two groundstate oxygen molecules are investigated theoretically at translational energies below ∼ 1K and in zero magnetic field. We present calculations for elastic and spinchanging inelastic collision rates for different isotopic combinations of oxygen atoms as a prelude to understanding their collisional stability in ultracold magnetic traps...
متن کاملUniversal rate constants for reactive collisions of ultracold molecules.
A simple quantum-defect model gives analytic expressions for the complex scattering length and threshold collision rates of ultracold molecules. If the probability of reaction in the short-range part of the collision is high, the model gives universal rate constants for s- and p-wave collisions that are independent of short-range dynamics. This model explains the magnitudes of the recently meas...
متن کاملRotational Feshbach resonances in ultracold molecular collisions.
In collisions at ultralow temperatures, molecules will possess Feshbach resonances, foreign to ultracold atoms, whose virtual excited states consist of rotations of the molecules. We estimate the mean spacing and mean widths of these resonant states, exploiting the fact the molecular collisions at low energy display chaotic motion. As examples, we consider the experimentally relevant molecules ...
متن کاملInelastic collisions of ultracold triplet Rb2 molecules in the rovibrational ground state
Exploring and controlling inelastic and reactive collisions on the quantum level is a main goal of the developing field of ultracold chemistry. For this, the preparation of precisely defined initial atomic and molecular states in tailored environments is necessary. Here we present experimental studies of inelastic collisions of metastable ultracold Rb2 molecules in an array of quasi-1D potentia...
متن کاملMolecule formation in ultracold atomic gases
This review describes recent experimental and theoretical advances in forming molecules in ultracold gases of trapped alkali metal atoms, both by magnetic tuning through Feshbach resonances and by photoassociation. Molecular Bose-Einstein condensation of long-range states of both boson dimers and fermion dimers was achieved in 2002-3. Condensates of boson dimers were found to be short-lived, bu...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2001