Time dependent hamiltonian in a rotating frame approximation
See original GitHub issueI’ve got this code which uses a rotating frame approximation. I got it to work when the Hamiltonian was time independent, but now I’m trying to implement a time dependent Hamiltonian and nothing happens to the graph. I understand how to do this, but I’m not sure how it differs when using a rotating frame approximation.
h = 6.62607015e-34
b = 0.1786195317554453 #magnetic field
b_AC = 3.572390635108906e-05 #oscillating magnetic field
g = 2 #g-factor
u = 9.274E-24 #bohr magneton
w = g*u*b/h #omega
w0 = 5e9 # omega0 is the rotating frame frequency
gamma_phi = 999000
gamma_minus = 1000
epsilon = g*u*b/h*(2*cmath.pi)
Delta = g*u*b_AC/h*(2*cmath.pi)
H0 = (w-w0)*epsilon/2 * sz #+ Delta/2*sy
def pulse(t0,t):
return np.heaviside(t0,2e-9)
def H1_coeff(t,args):
t0=args['t0']
phi=args['phi']
return Delta*pulse(t0,t)*np.sin((w-w0)*t+phi)
H = [H0,[sx,H1_coeff]]
times=np.linspace(0, 0.0001, 1000)
#our initial qubit state
state0=(state_z_plus)/(np.sqrt(1))
Issue Analytics
- State:
- Created 3 years ago
- Comments:8 (4 by maintainers)
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Top GitHub Comments
Thank you for your feedback. I was able to get the results I wanted. Just to provide some closure, I’m sending a photo
No, I’m using
w-w0
just to show that the code works fine with my suggested changes inpulse(t0,t)
. It is just the numbers that are wrong.First, please check the equation you are using again because (I guess)
H0
should be(w-w0)/2 * sz
and not the one you give in the code above. In your definition,w-w0
andepsilon
is the same thing. The drive frequency (in sinus function) should match withH0
.Second, it not clear to me what you want to achieve with this. If the drive frequency matches the system frequency (both
w-w0
here), H0 is exactly 0 in the rotating frame.