#!/usr/bin/env python3 # -*- coding: utf-8 -*- """ Quantum Eraser – GUI (shots / nphi / save / show) Author: ChatGPT Install: pip install "qiskit==1.2.*" "qiskit-aer==0.15.*" matplotlib numpy Run: python quantum_eraser_gui.py What it does: - Lets you set shots, nphi, and toggle "save" and "show" from a simple GUI. - Runs the delayed-choice quantum eraser simulation (AerSimulator). - Shows a live plot of P(s=0|i=+) and P(s=0|i=-). - If "save" is checked, writes: out/binary_phi_XX.txt (binary stream for S per phase) out/eraser_probs.csv out/eraser_plot.png """ import os import math import threading import tkinter as tk from tkinter import ttk, messagebox, filedialog import numpy as np import matplotlib matplotlib.use("TkAgg") import matplotlib.pyplot as plt from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg from qiskit import QuantumCircuit, transpile from qiskit_aer import AerSimulator # ------------------- Core experiment ------------------- def eraser_run(phi: float, erase: bool=True, shots: int=4000, seed: int=1234): """Return counts + memory list (bitstrings 'i s').""" qc = QuantumCircuit(2,2) # q0=S, q1=I; c0=S, c1=I qc.h(0) qc.rz(phi, 0) qc.cx(0,1) qc.h(0) if erase: qc.h(1) # measure I in X-basis qc.measure(0,0) qc.measure(1,1) backend = AerSimulator(seed_simulator=seed) tqc = transpile(qc, backend=backend, optimization_level=3) job = backend.run(tqc, shots=shots, memory=True) res = job.result() return res.get_counts(), res.get_memory() def conditional_prob(counts, i_bit='0'): tot = n0 = 0 for k, v in counts.items(): i, s = k[0], k[1] if i == i_bit: tot += v if s == '0': n0 += v return (n0 / tot) if tot else 0.0 def save_binary(memory, path): bits = ''.join(m[1] for m in memory) # only S (second bit) os.makedirs(os.path.dirname(path), exist_ok=True) with open(path, 'w') as f: f.write(bits) def save_csv(phi_list, p_plus, p_minus, path): os.makedirs(os.path.dirname(path), exist_ok=True) import csv with open(path, 'w', newline='') as f: w = csv.writer(f) w.writerow(['phi','P(s=0|i=+)','P(s=0|i=-)']) for phi,a,b in zip(phi_list,p_plus,p_minus): w.writerow([phi,a,b]) def visibility(vals): if not vals: return 0.0 vmax, vmin = max(vals), min(vals) denom = vmax + vmin return (vmax - vmin) / denom if denom else 0.0 # ------------------- GUI Application ------------------- class EraserGUI(tk.Tk): def __init__(self): super().__init__() self.title("Quantum Eraser – GUI") self.geometry("900x650") # Defaults self.var_shots = tk.IntVar(value=4000) self.var_nphi = tk.IntVar(value=13) self.var_save = tk.BooleanVar(value=True) self.var_show = tk.BooleanVar(value=True) self.var_outdir = tk.StringVar(value="out") self.var_seed = tk.IntVar(value=1234) # Controls frm = ttk.Frame(self, padding=10) frm.pack(side=tk.TOP, fill=tk.X) ttk.Label(frm, text="shots:").grid(row=0, column=0, sticky="w") ttk.Entry(frm, textvariable=self.var_shots, width=8).grid(row=0, column=1, padx=5) ttk.Label(frm, text="nphi:").grid(row=0, column=2, sticky="w") ttk.Entry(frm, textvariable=self.var_nphi, width=8).grid(row=0, column=3, padx=5) ttk.Checkbutton(frm, text="save", variable=self.var_save).grid(row=0, column=4, padx=10) ttk.Checkbutton(frm, text="show", variable=self.var_show).grid(row=0, column=5, padx=10) ttk.Label(frm, text="outdir:").grid(row=1, column=0, sticky="w", pady=5) out_entry = ttk.Entry(frm, textvariable=self.var_outdir, width=24) out_entry.grid(row=1, column=1, columnspan=3, sticky="we", padx=5, pady=5) ttk.Button(frm, text="Browse…", command=self.choose_outdir).grid(row=1, column=4, sticky="w") ttk.Label(frm, text="seed:").grid(row=1, column=5, sticky="e") ttk.Entry(frm, textvariable=self.var_seed, width=10).grid(row=1, column=6, padx=5) self.btn_run = ttk.Button(frm, text="Run", command=self.on_run_clicked) self.btn_run.grid(row=0, column=6, padx=10) # Figure self.fig = plt.Figure(figsize=(7,4.5)) self.ax = self.fig.add_subplot(111) self.ax.set_title("Quantum Eraser – P(s=0|i=±)") self.ax.set_xlabel("φ (radiani)") self.ax.set_ylabel("Probabilitate") self.line_plus, = self.ax.plot([], [], marker='o', label="P(s=0|i=+)") self.line_minus, = self.ax.plot([], [], marker='s', label="P(s=0|i=-)") self.ax.legend() self.ax.grid(True, linestyle='--', alpha=0.4) self.canvas = FigureCanvasTkAgg(self.fig, master=self) self.canvas.get_tk_widget().pack(side=tk.TOP, fill=tk.BOTH, expand=True) # Status self.status = tk.StringVar(value="Ready.") ttk.Label(self, textvariable=self.status, anchor="w", padding=8).pack(side=tk.BOTTOM, fill=tk.X) self._running = False def choose_outdir(self): d = filedialog.askdirectory(title="Select output directory") if d: self.var_outdir.set(d) def on_run_clicked(self): if self._running: messagebox.showinfo("Info", "Experiment already running.") return try: shots = int(self.var_shots.get()) nphi = int(self.var_nphi.get()) if shots <= 0 or nphi <= 1: raise ValueError except Exception: messagebox.showerror("Error", "Invalid shots or nphi.") return self._running = True self.btn_run.config(state=tk.DISABLED) self.status.set("Running…") threading.Thread(target=self.run_experiment_threadsafe, daemon=True).start() def run_experiment_threadsafe(self): try: self.run_experiment() except Exception as e: self.status.set(f"Error: {e}") messagebox.showerror("Error", str(e)) finally: self._running = False self.btn_run.config(state=tk.NORMAL) def run_experiment(self): shots = int(self.var_shots.get()) nphi = int(self.var_nphi.get()) save = bool(self.var_save.get()) showp = bool(self.var_show.get()) outdir= self.var_outdir.get() seed = int(self.var_seed.get()) os.makedirs(outdir, exist_ok=True) phis = np.linspace(0.0, 2.0*math.pi, nphi) p_plus, p_minus = [], [] # clear plot self.line_plus.set_data([], []) self.line_minus.set_data([], []) self.ax.relim(); self.ax.autoscale_view() self.canvas.draw_idle() for idx, phi in enumerate(phis): counts, memory = eraser_run(phi, erase=True, shots=shots, seed=seed) p0_plus = conditional_prob(counts, '0') p0_minus = conditional_prob(counts, '1') p_plus.append(p0_plus); p_minus.append(p0_minus) # update live plot self.line_plus.set_data(phis[:idx+1], p_plus) self.line_minus.set_data(phis[:idx+1], p_minus) self.ax.relim(); self.ax.autoscale_view() self.canvas.draw_idle() # save binary per phase if save: save_binary(memory, os.path.join(outdir, f"binary_phi_{idx:02d}.txt")) self.status.set(f"φ={phi:.3f} • P(+)= {p0_plus:.3f} • P(-)= {p0_minus:.3f} • step {idx+1}/{nphi}") # save CSV and PNG if save: import csv with open(os.path.join(outdir, "eraser_probs.csv"), "w", newline="") as f: w = csv.writer(f) w.writerow(['phi','P(s=0|i=+)','P(s=0|i=-)']) for phi,a,b in zip(phis, p_plus, p_minus): w.writerow([phi, a, b]) self.fig.savefig(os.path.join(outdir, "eraser_plot.png"), dpi=160) Vp = visibility(p_plus); Vm = visibility(p_minus) self.status.set(f"Done. Vizibilitate: V(+)≈{Vp:.3f}, V(-)≈{Vm:.3f}") if showp: # keep the window open; nothing extra needed in Tk GUI pass def main(): app = EraserGUI() app.mainloop() if __name__ == "__main__": main()