91 lines
3.2 KiB
Python
91 lines
3.2 KiB
Python
|
from plot import *
|
||
|
|
import scqubits as scq
|
||
|
|
import qutip as qt
|
||
|
|
|
||
|
|
# flux = scq.FluxQubit()
|
||
|
|
fluxonium = scq.Fluxonium(EJ=9, EC=3, EL=0.5, flux=1, cutoff=100)
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
def _plot_transmon_n_wavefunctions(qubit: scq.Transmon, fig_ax, which=[0,1]):
|
||
|
|
fig, ax = fig_ax
|
||
|
|
ax.set_ylabel(r"$|\psi_i(n)|^2$")
|
||
|
|
ax.set_xlabel(r"$n$")
|
||
|
|
colors = "brgy"
|
||
|
|
for i in which:
|
||
|
|
wf = qubit.numberbasis_wavefunction(which=i)
|
||
|
|
x = wf.basis_labels
|
||
|
|
y = wf.amplitudes
|
||
|
|
offset = (len(which)/2 - i) * 0.2
|
||
|
|
ax.bar(x-offset, y, width=0.2, align='center', label=f"$i={i}$")
|
||
|
|
xlim = (-4, 4)
|
||
|
|
ax.set_xlim(*xlim)
|
||
|
|
ax.set_xticks(np.arange(xlim[0], xlim[1]+1))
|
||
|
|
|
||
|
|
def _plot_transmon(qubit: scq.Transmon, ngs, fig, axs):
|
||
|
|
_,_ = qubit.plot_evals_vs_paramvals("ng", ngs, fig_ax=(fig, axs[0]), evals_count=5, subtract_ground=False)
|
||
|
|
_,_ = qubit.plot_wavefunction(fig_ax=(fig, axs[1]), which=[0, 1, 2], mode="abs_sqr")
|
||
|
|
_plot_transmon_n_wavefunctions(qubit, (fig, axs[2]), which=[0, 1, 2])
|
||
|
|
qubit.ng = 0.5
|
||
|
|
_plot_transmon_n_wavefunctions(qubit, (fig, axs[3]), which=[0, 1, 2])
|
||
|
|
qubit.ng = 0
|
||
|
|
|
||
|
|
|
||
|
|
def transmon_cpb():
|
||
|
|
EC = 1
|
||
|
|
qubit = scq.Transmon(EJ=30, EC=EC, ng=0, ncut=30)
|
||
|
|
ngs = np.linspace(-2, 2, 200)
|
||
|
|
fig, axs = plt.subplots(4, 3, squeeze=True, figsize=(full,full))
|
||
|
|
axs = axs.T
|
||
|
|
qubit.ng = 0
|
||
|
|
qubit.EJ = 0.1 * EC
|
||
|
|
title = lambda x: f"$E_J/E_C = {x}$"
|
||
|
|
_plot_transmon(qubit, ngs, fig, axs[0])
|
||
|
|
axs[0][0].set_title("Cooper-Pair-Box\n"+title(qubit.EJ))
|
||
|
|
|
||
|
|
qubit.EJ = EC
|
||
|
|
_plot_transmon(qubit, ngs, fig, axs[1])
|
||
|
|
axs[1][0].set_title("Quantronium\n"+title(qubit.EJ))
|
||
|
|
|
||
|
|
qubit.EJ = 20 * EC
|
||
|
|
_plot_transmon(qubit, ngs, fig, axs[2])
|
||
|
|
axs[2][0].set_title("Transmon\n"+title(qubit.EJ))
|
||
|
|
|
||
|
|
for ax in axs[1:,:].flatten(): ax.set_ylabel("")
|
||
|
|
for ax in axs[:,0].flatten():
|
||
|
|
ax.set_xticks([-2, -1, -0.5, 0, 0.5, 1, 2])
|
||
|
|
ax.set_xticklabels(["-2", "-1", "", "0", "", "1", "2"])
|
||
|
|
ylim = ax.get_ylim()
|
||
|
|
ax.vlines([-1, -0.5], ymin=ylim[0], ymax=ylim[1], color="#aaa", linestyle="dotted")
|
||
|
|
axs[0][2].legend()
|
||
|
|
fig.tight_layout()
|
||
|
|
return fig
|
||
|
|
|
||
|
|
export(transmon_cpb(), "qubit_transmon")
|
||
|
|
|
||
|
|
|
||
|
|
def flux_onium():
|
||
|
|
fig, axs = plt.subplots(1, 2, squeeze=True, figsize=(full,full))
|
||
|
|
fluxs = np.linspace(-2, 2, 101)
|
||
|
|
EJ = 35.0
|
||
|
|
alpha = 0.6
|
||
|
|
fluxqubit = scq.FluxQubit(EJ1 = EJ,
|
||
|
|
EJ2 = EJ,
|
||
|
|
EJ3 = alpha*EJ,
|
||
|
|
ECJ1 = 1.0,
|
||
|
|
ECJ2 = 1.0,
|
||
|
|
ECJ3 = 1.0/alpha,
|
||
|
|
ECg1 = 50.0,
|
||
|
|
ECg2 = 50.0,
|
||
|
|
ng1 = 0.0,
|
||
|
|
ng2 = 0.0,
|
||
|
|
flux = 0.5,
|
||
|
|
ncut = 10)
|
||
|
|
fluxqubit.plot_evals_vs_paramvals("flux", fluxs, evals_count=5, subtract_ground=True, fig_ax=(fig, axs[0]))
|
||
|
|
|
||
|
|
fluxonium = scq.Fluxonium(EJ=9, EC=3, EL=0.5, flux=1, cutoff=100)
|
||
|
|
fluxonium.plot_evals_vs_paramvals("flux", fluxs, evals_count=5, subtract_ground=True, fig_ax=(fig, axs[1]))
|
||
|
|
return fig
|
||
|
|
|
||
|
|
export(flux_onium(), "qubit_flux_onium")
|