Qutip 可视化

# QuTiP 可视化 ## 布洛赫球 (Bloch Sphere) 在布洛赫球上可视化量子比特态。 ### 基本用法 python from qutip import * import matplotlib.pyplot as plt # 创建布洛赫球 b = Bloch() # 添加态 psi = (basis(2, 0) + basis(2, 1)).unit() b.add_states(psi) # 添加向量 b.add_vectors([1, 0, 0]) # X轴 # 显示 b.show() ### 多态显示 python # 添加多个态 states = [(basis(2, 0) + basis(2, 1)).unit(), (basis(2, 0) + 1j*basis(2, 1)).unit()] b.add_states(states) # 添加点 b.add_points([[0, 1, 0], [0, -1, 0]]) # 自定义颜色 b.point_color = ['r', 'g'] b.point_marker = ['o', 's'] b.point_size = [20, 20] b.show() ### 动画 python # 动画演示态演化 states = result.states # 来自 sesolve/mesolve b = Bloch() b.vector_color = ['r'] b.view = [-40, 30] # 视角 # 创建动画 from matplotlib.animation import FuncAnimation def animate(i): b.clear() b.add_states(states[i]) b.make_sphere() return b.axes anim = FuncAnimation(b.fig, animate, frames=len(states), interval=50, blit=False, repeat=True) plt.show() ### 自定义 python b = Bloch() # 球体外观 b.sphere_color = '#FFDDDD' b.sphere_alpha = 0.1 b.frame_alpha = 0.1 # 坐标轴 b.xlabel = ['$|+\\rangle$', '$|-\\rangle$'] b.ylabel = ['$|+i\\rangle$', '$|-i\\rangle$'] b.zlabel = ['$|0\\rangle$', '$|1\\rangle$'] # 字体大小 b.font_size = 20 b.font_color = 'black' # 视角 b.view = [-60, 30] # 保存图片 b.save('bloch.png') ## 维格纳函数 (Wigner Function) 相空间准概率分布。 ### 基本计算 python # 创建态 psi = coherent(N, alpha) # 计算维格纳函数 xvec = np.linspace(-5, 5, 200) W = wigner(psi, xvec, xvec) # 绘图 fig, ax = plt.subplots(1, 1, figsize=(6, 6)) cont = ax.contourf(xvec, xvec, W, 100, cmap='RdBu') ax.set_xlabel('Re(α)') ax.set_ylabel('Im(α)') plt.colorbar(cont, ax=ax) plt.show() ### 特殊颜色映射 python # 维格纳颜色映射强调负值 from qutip import wigner_cmap W = wigner(psi, xvec, xvec) fig, ax = plt.subplots() cont = ax.contourf(xvec, xvec, W, 100, cmap=wigner_cmap(W)) ax.set_title('Wigner Function') plt.colorbar(cont) plt.show() ### 3D 曲面图 python from mpl_toolkits.mplot3d import Axes3D X, Y = np.meshgrid(xvec, xvec) fig = plt.figure(figsize=(8, 6)) ax = fig.add_subplot(111, projection='3d') ax.plot_surface(X, Y, W, cmap='RdBu', alpha=0.8) ax