Bose-Einstein Condensation and Bose Glasses in an S = 1 Organo-metallic quantum magnet

Zapf, Vivien¹ 

[1] Los Alamos National Laboratory

关键词: ANTIFERROMAGNETISM;    BOSE-EINSTEIN CONDENSATION;    BOSONS;    FLUCTUATIONS;    GLASS;    MAGNETIC FIELDS;    MAGNETISM;    MAGNETS;    TESTING;    THERMODYNAMICS;    TUNING;    WAVE FUNCTIONS;   

DOI  :  10.2172/1042992
RP-ID  :  LA-UR-12-21827
PID  :  OSTI ID: 1042992
Others  :  TRN: US1203070

美国|英语

来源: SciTech Connect

【 摘 要 】

I will speak about Bose-Einstein condensation (BEC) in quantum magnets, in particular the compound NiCl2-4SC(NH2)2. Here a magnetic field-induced quantum phase transition to XY antiferromagnetism can be mapped onto BEC of the spins. The tuning parameter for BEC transition is the magnetic field rather than the temperature. Some interesting phenomena arise, for example the fact that the mass of the bosons that condense can be strongly renormalized by quantum fluctuations. I will discuss the utility of this mapping for both understanding the nature of the quantum magnetism and testing the thermodynamic limit of Bose-Einstein Condensation. Furthermore we can dope the system in a clean and controlled way to create the long sought-after Bose Glass transition, which is the bosonic analogy of Anderson localization. I will present experiments and simulations showing evidence for a new scaling exponent, which finally makes contact between theory and experiments. Thus we take a small step towards the difficult problem of understanding the effect of disorder on bosonic wave functions.