Lindblad operator

A Lindblad operator describes one dissipative contribution to a Markovian master equation for a density operator. In the common convention,with $\hslash =1$. Absorbing a rate into $L_{\alpha }$ gives it square-root-rate units.

For a two-level system, $L=\sqrt{\gamma }|0⟩⟨1|$ models decay from the excited state, while a diagonal operator can describe dephasing. The gain and anticommutator terms together preserve trace; retaining only the first would not define the same unconditional evolution. The operators are not unique, and a stochastic jump interpretation needs a specified monitoring of the environment. The physical object is the complete Lindbladian, including its Hamiltonian and dissipative parts.