Bloch spectrum

Noun

• A concept relating to energy spectra. Let H be the one-dimensional Schrödinger equation operator $H\; =\; -\; \backslash frac\{d^2\}\{dx^2\}\; +\; U\_\backslash alpha,$ where U_α is a periodic function of period α. The Bloch spectrum of H is the set of values E for which all the solutions of (H − E)φ = 0 are bounded on the whole real axis.