Anatomy of a polarization switch of a vertical-cavity semiconductor laser

Using a streak camera we have measured the three Stokes polarization parameters during a polarization switch of a vertical-cavity semiconductor laser. The switch occurs along a corkscrew path on the Poincare sphere and takes on average a few nanoseconds; this value agrees with a theoretical treatment based upon the Fokker-Planck equation.     

Preparation of bis(beta-trimethylsilylethanesulfonyl)imide and its use in the synthesis of protected amine derivatives

Bis(beta-trimethylsilylethanesulfonyl)imide (SES(2)NH) can be easily prepared in 85% yield by alkylation of the trianion of bismethanesulfonimide with 2 equiv of commerically available (iodomethyl)trimethylsilane. This synthon undergoes effective Mitsunobu alkylation reactions with both primary and secondary alcohols to afford the corresponding bis-SES imides. These imides can be selectively cleaved to the mono-SES-protected amines, and in addition undergo a one-pot cleavage/N-alkylation to afford SES derivatives of secondary amines.