44 lines
910 B
Python
44 lines
910 B
Python
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import numpy as np
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import matplotlib.pyplot as plt
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from pyqcs import State, sample
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from transfer_matrix import T_time_slice
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from hamiltonian import H
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nqbits = 4
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g = 0.5
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N = 400
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t_stop = 9
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delta_t = 0.05
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qbits = list(range(nqbits))
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n_sample = 200
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measure = 0b10
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results_qc = []
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print()
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for t in np.arange(0, t_stop, delta_t):
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# QC simulation
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state = State.new_zero_state(nqbits)
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for _ in range(N):
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state = T_time_slice(qbits, t, g, N) * state
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result = sample(state, measure, n_sample)
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results_qc.append(result[0] / n_sample)
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# Simulation using matrices
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#np_
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print(f"simulating... {int(t/t_stop*100)} % ", end="\r")
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print()
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print("done.")
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plt.plot(np.arange(0, t_stop, delta_t), results_qc)
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plt.xlabel("t")
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plt.ylabel(r"$|0\rangle$ probability amplitude for second spin")
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plt.title(f"{nqbits} site spin chain with g={g} coupling to external field")
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plt.show()
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