Tossup

Sato et al. showed that this macroscopic state occurs when recombining a helium plasma with a neutral gas, and Furukane (“foo-roo-KAH-nay”) et al. predicted that this state only occurs when three-body recombinations dominate. Velocity coherence and this state are needed for Dicke superradiance to occur. One kind of frequency standard induces this state in hydrogen by using 21-centimeter photons to flip (10[1])electron spin from antiparallel to parallel. Since systems in this state experience a decrease in entropy (-5[2])when increasing (10[2])internal energy, this state (10[1])causes amplification (10[1])of (10[1])radiation (-5[1])and is an example of negative temperature. (10[2]-5[1])An (10[1])yttrium (10[1])aluminum garnet acts as a (-5[1])gain medium for this (10[1])state (-5[1])to occur (10[1])in neodymium ions via pumping. For 10 points, more particles are in an excited (10[1])state (10[1])than the ground state (10[1])in what state that causes stimulated emission in lasers? (10[2])■END■ (10[3])

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