constrained_layout=True)
l = len(gate)
for ax, index in zip(axes, [0, l // 4, l // 2, 3 * l // 4, -1]):
ax.plot(field[index] * 1e3, res['original'][index], '+')
ax.plot(field[index] * 1e3, res['xx'][index])
ax.axvline(0)
ax.set_xlabel('Field (mT)')
ax.set_ylabel('Resistance (Ω)')
plt.show()
# Extract the density and mobility and compute useful quantities.
density = extract_density(field, res['xy'], FIELD_BOUNDS, PLOT_DENSITY_FIT)
if PLOT_DENSITY_FIT:
plt.show()
mobility, std_mob = extract_mobility(field, res['xx'], res['yy'], density,
GEOMETRIC_FACTORS[GEOMETRY])
density, std_density = density
mass = EFFECTIVE_MASS * cs.electron_mass
htr = htr_from_mobility_density(mobility, density, mass)
diff = diffusion_constant_from_mobility_density(mobility, density, mass)
# If requested plot the Htr that tells us in what range the WAL can be valid.
if PLOT_HTR:
f, axes = plt.subplots(1, 3, figsize=(10, 5), constrained_layout=True)
for ax, x, y, x_lab, y_lab in zip(
axes, (gate, density / 1e4, density / 1e4),
(density / 1e4, mobility * 1e4, htr * 1e3),
('Gate voltage (V)', 'Density (cm$^{-2}$)', 'Density (cm$^{-2}$)'),
('Density (cm$^{-2}$)', 'Mobility (cm$^{-2}$V${^-1}$s$^{-1}$)',
'Htr (mT)')):
val = val
res[k] = convert_lock_in_meas_to_diff_res(val, PROBE_CURRENT)
if GATE_COLUMN is not None:
gate = gate[:, 0]
if "xy" in res:
density, std_density = extract_density(field, res["xy"], FIELD_BOUNDS,
PLOT_DENSITY_FIT)
print(f"{density / 1e4:g}")
if PLOT_DENSITY_FIT:
plt.show()
if "xx" in res and "yy" in res:
mobility = extract_mobility(field, res["xx"], res["yy"], density,
GEOMETRIC_FACTORS[GEOMETRY])
if len(res) == 3:
mass = EFFECTIVE_MASS * cs.electron_mass
vf = fermi_velocity_from_density(density, mass)
mft = mean_free_time_from_mobility(mobility, mass)
diff = diffusion_constant_from_mobility_density(mobility, density, mass)
if RESULT_PATH:
df = pd.DataFrame({
"Gate voltage (V)": gate,
"Density (m^-2)": density,
"Stderr density (m^-2)": std_density,
"Mobility xx (m^2V^-1s^-1)": mobility[0],
"Mobility yy (m^2V^-1s^-1)": mobility[1],
"Mean free time xx (s)": mft[0],