Anomalous weak values via a single photon detection

• URL: http://arxiv.org/abs/2103.12602v1
• Date: Tue, 23 Mar 2021 14:57:55 GMT
• Title: Anomalous weak values via a single photon detection
• Authors: E. Rebufello, F. Piacentini, A. Avella, M. A. de Souza, M. Gramegna, J. Dziewior, E. Cohen, L. Vaidman, I. P. Degiovanni, M. Genovese
• Abstract summary: We present the first experiment measuring anomalous weak values with just a single click. The measurement uncertainty is significantly smaller than the gap between the measured weak value and the nearest eigenvalue. This result represents a breakthrough in understanding quantum measurement foundations, paving the way to further applications of weak values to quantum photonics.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Is it possible that a measurement of a spin component of a spin-1/2 particle yields the value 100? In 1988 Aharonov, Albert and Vaidman argued that upon pre- and postselection of particular spin states, weakening the coupling of a standard measurement procedure ensures this paradoxical result. This theoretical prediction, called weak value, was realized in numerous experiments, but its meaning remains very controversial, since its "anomalous" nature, i.e. the possibility to exceed the eigenvalues range, as well as its "quantumness" are debated. We address these questions by presenting the first experiment measuring anomalous weak values with just a single click, without any statistics. The measurement uncertainty is significantly smaller than the gap between the measured weak value and the nearest eigenvalue. Beyond clarifying the meaning of weak values, this result represents a breakthrough in understanding quantum measurement foundations, paving the way to further applications of weak values to quantum photonics.

Related papers

• Certifying the quantumness of a nuclear spin qudit through its uniform precession [28.4073170440133]
  We certify the quantumness of exotic states of a nuclear spin through its uniform precession. The experiment is performed on a single spin-7/2 $123$Sb nucleus implanted in a silicon nanoelectronic device.
  arXiv  Detail & Related papers  (2024-10-10T06:20:41Z)
• Association between quantum paradoxes based on weak values and a realistic interpretation of quantum measurements [0.0]
  Many quantum paradoxes based on a realistic view of weak values were discussed in the last decades. We show that the realistic view of the weak values present in these works is equivalent to a realistic view of quantum measurements.
  arXiv  Detail & Related papers  (2024-02-15T11:07:46Z)
• Quantum Discord Witness with Uncharacterized Devices [18.751513188036334]
  We propose a new approach using uncharacterized measurements to witness quantum discord of an unknown bipartite state within arbitrary dimension system. The feature of high robustness against device imperfections, such as loss-tolerance and error-tolerance, shows our method is experimentally feasible.
  arXiv  Detail & Related papers  (2023-03-20T14:51:53Z)
• Finitely Repeated Adversarial Quantum Hypothesis Testing [22.102728605081534]
  We formulate a passive quantum detector based on a quantum hypothesis testing framework under the setting of finite sample size. Under the assumption that the attacker adopts separable optimal strategies, we derive that the worst-case average error bound converges to zero exponentially. We adopt our formulations upon a case study of detection with quantum radars.
  arXiv  Detail & Related papers  (2022-12-02T17:08:17Z)
• Experimental demonstration of optimal unambiguous two-out-of-four quantum state elimination [52.77024349608834]
  A core principle of quantum theory is that non-orthogonal quantum states cannot be perfectly distinguished with single-shot measurements. Here we implement a quantum state elimination measurement which unambiguously rules out two of four pure, non-orthogonal quantum states.
  arXiv  Detail & Related papers  (2022-06-30T18:00:01Z)
• The Quantum Eraser from a Weak Values Perspective [0.0]
  The interference fringes that appear when measuring certain spin states, which can then be 'erased' when measuring other spin states, are shown to be anomalous weak values that depend on particular post-selection choices. Specifically, claims about the choice of spin-state retrocausally' influencing the choice of slit(s) for the particles to travel through are discredited.
  arXiv  Detail & Related papers  (2022-01-25T13:45:04Z)
• Tight Exponential Analysis for Smoothing the Max-Relative Entropy and for Quantum Privacy Amplification [56.61325554836984]
  The max-relative entropy together with its smoothed version is a basic tool in quantum information theory. We derive the exact exponent for the decay of the small modification of the quantum state in smoothing the max-relative entropy based on purified distance.
  arXiv  Detail & Related papers  (2021-11-01T16:35:41Z)
• Experimental Test of Sequential Weak Measurements for Certified Quantum Randomness Extraction [0.0]
  We study the feasibility of weak measurements to extract randomness from a single state. We show that the weak measurements are real, but can improve the performance of randomness generation only in close-to-ideal conditions.
  arXiv  Detail & Related papers  (2021-01-28T15:46:58Z)
• Weak Measurement of Superconducting Qubit Reconciles Incompatible Operators [1.651690213572386]
  Weak measurements are shown to obey an uncertainty relation cast in terms of entropies. A weak measurement can reconcile two strong measurements' incompatibility, via backaction on the state. We provide experimental support for the physical interpretation of the weak value as a determinant of a weak measurement's ability to reconcile operations.
  arXiv  Detail & Related papers  (2020-08-20T18:00:05Z)
• Maximum refractive index of an atomic medium [58.720142291102135]
  All optical materials with a positive refractive index have a value of index that is of order unity. Despite the giant response of an isolated atom, we find that the maximum index does not indefinitely grow with increasing density. We propose an explanation based upon strong-disorder renormalization group theory.
  arXiv  Detail & Related papers  (2020-06-02T14:57:36Z)
• Weak values from path integrals [0.0]
  We show how Feynman propagators can in principle be experimentally inferred from weak value measurements. We obtain expressions for weak values parsing unambiguously the quantum and the classical aspects of weak couplings between a system and a probe.
  arXiv  Detail & Related papers  (2020-02-03T15:45:15Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.