v0.2.8

WaveguideQED v0.2.8

Diff since v0.2.7

Added expect_waveguide() to get expectation value of waveguide operators.
Small bugfix for multiplying LazyTensors with waveguide operators in them

Closed issues:

• Question about Delayed Operators (#49)
• waveguide_evolution for time-dependent Hamiltonian (#53)