Multimode Opto-mechanical cavity

[MUHAMMAD TAHIR NASEEM]

Hi,

I have just started to learn Qutip, I have very basic question.

I want to define Destroy (Annihilation) operators for two optical modes and two mechanical modes for opto-mechanical setup. I know how to write them for single mode

N = 8
a = tensor(destroy(N), qeye(4))
b = tensor(qeye(N), destroy(4))

I will really appreciate the help.

[M Cotrufo]

You just need to keep using the tensor() function, but with 4 entries. You need to write something like

Nopt1 = 8

Nopt2 = 8

Nmech1 = 4

Nmech2 = 4

a1 = tensor(destroy(Nopt1), qeye(Nopt2), qeye(Nmech1), qeye(Nmech2 ))

a2 = tensor(qeye(Nopt1),destroy(Nopt2), qeye(Nmech1), qeye(Nmech2 ))

b1 = tensor(qeye(Nopt1), qeye(Nopt2), destroy(Nmech1),qeye(Nmech2 ))

b2 = tensor(qeye(Nopt1), qeye(Nopt2),qeye(Nmech1), destroy(Nmech2))