Papers
Topics
Authors
Recent
Gemini 2.5 Flash
Gemini 2.5 Flash 97 tok/s
Gemini 2.5 Pro 39 tok/s Pro
GPT-5 Medium 29 tok/s
GPT-5 High 28 tok/s Pro
GPT-4o 93 tok/s
GPT OSS 120B 462 tok/s Pro
Kimi K2 215 tok/s Pro
2000 character limit reached

Entanglement-enabled delayed choice experiment (1206.4348v1)

Published 19 Jun 2012 in quant-ph

Abstract: Complementarity, that is the ability of a quantum object to behave either as a particle or as a wave, is one of the most intriguing features of quantum mechanics. An exemplary Gedanken experiment, emphasizing such a measurement-dependent nature, was suggested by Wheeler using single photons. The subtleness of the idea lies in the fact that the output beam-splitter of a Mach-Zehnder interferometer is put in or removed after a photon has already entered the interferometer, thus performing a delayed test of the wave-particle complementary behavior. Recently, it was proposed that using a quantum analogue of the output beam-splitter would permit carrying out this type of test after the detection of the photon and observing wave-particle superposition. In this paper we describe an experimental demonstration of these predictions using another extraordinary property of quantum systems, entanglement. We use a pair of polarization entangled photons composed of one photon whose nature (wave or particle) is tested, and of a corroborative photon that allows determining which one, or both, of these two aspects is being tested. This corroborative photon infers the presence or absence of the beam-splitter and until it is measured, the beam-splitter is in a superposition of these two states, making it a quantum beam-splitter. When the quantum beam-splitter is in the state present or absent, the interferometer reveals the wave or particle nature of the test photon, respectively. Furthermore, by manipulating the corroborative photon, we can continuously morph, via entanglement, the test photon from wave to particle behavior even after it was detected. This result underlines the fact that a simple vision of light as a classical wave or a particle is inadequate.

Citations (186)
List To Do Tasks Checklist Streamline Icon: https://streamlinehq.com

Collections

Sign up for free to add this paper to one or more collections.

Summary

  • The paper presents an experiment using entangled photons and a quantum beam-splitter to demonstrate wave-particle duality and complementarity in an entanglement-enabled delayed choice setting.
  • Key findings include the ability to 'morph' the test photon's wave-particle nature by measuring its entangled partner and verification of non-classical correlations via Bell inequality violation.
  • The study provides new insights into quantum measurement and suggests potential applications for manipulating entanglement in future quantum computing and communication technologies.

Entanglement-Enabled Delayed Choice Experiment: An Overview

This paper presents an intricate experimental demonstration of quantum mechanics's complementarity and entanglement using an innovative approach toward the famous delayed choice experiment initially proposed by Wheeler. The research predominantly focuses on manifesting wave-particle duality through a quantum beam-splitter (QBS) apparatus by leveraging the principles of quantum entanglement. Concerning both theoretical insights and practical execution, the paper enriches our understanding of complementarity and the nuanced interpretations of quantum phenomena.

Quantum Delayed Choice and Complementarity

The concept of complementarity in quantum mechanics, as hypothesized by Niels Bohr, suggests that quantum entities exhibit either wave-like or particle-like characteristics contingent on the measurement apparatus. Wheeler's delayed choice experiment of the Mach-Zehnder interferometer articulated that the decision to measure a quantum object's path or interference, via a beam-splitter positioned at the interferometer's exit, could be delayed until after the object entered the interferometer, but prior to its detection.

Building from Wheeler's Gedankenexperiment, the research innovatively implements a quantum beam-splitter, integrating into the experimental framework a scenario where the configuration at the interferometer's exit is itself in a superposition state. By involving two entangled photons, where one photon's behavior gets tested (wave or particle) and the corroborative photon's measurement identifies the reality assessed, novel insights emerge regarding wave-particle superposition and its measurement implications.

Experimental Methodology and Key Findings

Key to the experiment is the entanglement between photon pairs, one designated as the test photon and the other as the corroborative photon. The quantum state of these photons gets modulated using polarization, and their states coherently entangle through a QBS setup. The behavior—wave-like or particle-like—of the test photon can theoretically be determined by the state of the corroborative photon, a notion that sustained until the corroborative photon is measured. This superposing of wave-particle nature upon post-measurement substantiates the complexity of defining light solely as a wave or particle.

Below are notable experimental observations derived from the experiment:

  • Quantum Beam-Splitter Implementation: By using polarization-dependent beam-splitters, distinct wave and particle behaviors could be revealed for different polarization states, with wave-particle behavior coherent superposition being preserved before measurement is ascertained.
  • Wave-Particle Morphing: The corroborative photon's measurement can ultimately project the test photon's nature into any desirable state, transitioning from wave to particle or vice versa.
  • Bell Inequalities Verification: A significant validation of the entanglement involved was the breach of Bell inequalities, which confirms the non-classical correlations between the photon pairs.

The experiments further addressed typical loopholes concerning local hidden variables and ensured that the supposed causal relations could not attribute to classical communication between photons, thus securing the experiment’s validity in terms of quantum mechanical behavior.

Implications and Future Directions

The implications of this paper are far-reaching in both theoretical considerations and experimental practicalities. By conclusively demonstrating indeterminacy in wave and particle classifications until measurement ensues, the research gives more granularity to the debates around quantum measurement, decoherence, and observer effect—all vital discussions in quantum mechanics and information theory.

The technology prototypes and concepts exhibited pave new paths for quantum computing and communication, especially in scenarios demanding quantum data processing that preserves entanglement. These findings stimulate further experimental pursuits into non-locality, quantum coherence, and decohering systems, suggesting that quantum applications can gain additional robustness from manipulating wave-particle duality.

Overall, this work reinforces the intricate behavior of quantum systems and highlights the profound implications these experiments have on understanding and utilizing quantum entanglement for future technological advancements.

Ai Generate Text Spark Streamline Icon: https://streamlinehq.com

Paper Prompts

Sign up for free to create and run paper prompts using GPT-5.

Dice Question Streamline Icon: https://streamlinehq.com

Follow-up Questions

We haven't generated follow-up questions for this paper yet.

Youtube Logo Streamline Icon: https://streamlinehq.com