We demonstrate a new cooling method in which a time-varying magnetic field gradient is applied to an ultracold spin mixture. This enables preparation of isolated spin distributions at positive and negative effective spin temperatures of ±50   pK. The spin system can also be used to cool other degrees of freedom, and we have used this coupling to cool an apparently equilibrated Mott insulator of...

We report on analytical and numerical results for the time evolution of a ~lattice! model of ferromagnetic particles after field inversion. Relaxation from the metastable phase occurs by superposition of two independent spin-flip processes: with probability 12p , the flip obeys the Metropolis rule at finite temperature, T , while the flip is performed at random, as for T→` , with probability p ...

(By measurement we mean all variables of a theoretical relation that determine the length have been quantitatively observed, no ROMs.) The skew above the electron skin depth of the scale length population determined an average scale length of the ‘‘EDRs’’ 80% higher than the upper bound stated in the ‘‘EDR’’ study’s abstract. This situation contributes another average multiplicative enhancement...

In this thesis, I study optical pumping as a powerful cooling tool for trapped ultra-cold atoms in a highly collisional regime. First application of optical pumping is a continuous loading scheme used to transfer atoms from a guided beam into a hybrid trap. Further, I introduce a Sisyphus cooling scheme based on radio-frequency transitions and optical pumping, operating simultaneously to the ac...

In the natural case of an hypervelocity impact on a planetary or asteroidal surface, two competing phenomena occur: partial or complete shock demagnetizat on of preexisting remanence and acquisition of shock remanent magnetization (SRM). In this paper, to better understand the effects of shock on the magnetic history of rocks, we simulate this natural case through laser shock experiments in con...

It is experimentally demonstrated that an adiabatic demagnetization-remagnetization in the laboratory frame, where the Zeeman order of abundant nuclei is first adiabatically converted into the dipolar order, and then, into the Zeeman order of rare nuclei, can significantly increase polarization of rare nuclei compared to the conventional cross-polarization technique.

The lowest temperatures ever measured have been produced by cascade adiabatic nuclear demagnetization of copper and rhodium. Ultimately, spontaneous antiferromagnetic ordering of rhodium nuclei is anticipated. High-sensitivity SQUID-NMR measurements at high nuclear polarization in low magnetic "elds have been used to study the mutual interactions between the nuclear spins of rhodium in the meta...

An algorithm was developed detect the partial demagnetization of permanent-magnet synchronous motors (PMSMs) under both stationary and nonstationary conditions. On basis recursive least-squares (RLS) method, vital component fault-related harmonics in current could be extracted on line, its proportion to fundamental regarded as indicator faults. The proposed is fairly easy realize substitute con...