We report the experimental detection of bulk topological invariants in nonunitary discrete-time quantum walks with single photons. The nonunitarity dynamics is enforced by periodically performing partial measurements on polarization walker photon, which effectively introduces loss to dynamics. invariant walk manifested quantized average displacement walker, probed monitoring photon loss. confirm properties system observing localized edge states at boundary regions different invariants....

Signaled by non-analyticities in the time evolution of physical observables, dynamic quantum phase transitions (DQPTs) emerge quench dynamics topological systems and possess an interesting geometric origin captured order parameters (DTOPs). In this work, we report experimental study DQPTs using discrete-time walks single photons. We simulate between distinct Floquet phases quantum-walk dynamics, experimentally characterize underlying DTOPs through interference-based measurements. The...

We experimentally simulate nonunitary quantum dynamics using a single-photon interferometric network and study the information flow between parity-time- (PT-)symmetric non-Hermitian system its environment. observe oscillations of quantum-state distinguishability complete retrieval in PT-symmetry-unbroken regime. then characterize detail critical phenomena near exceptional point separating PT-unbroken PT-broken regimes, demonstrate power-law behavior key quantities such as recurrence time....

Parity-time (PT)-symmetric Hamiltonians have widespread significance in non-Hermitian physics. A PT-symmetric Hamiltonian can exhibit distinct phases with either real or complex eigenspectrum, while the transition points between, so-called exceptional points, give rise to a host of critical behaviors that holds great promise for applications. For spatially periodic systems, PT symmetries are commonly characterized and observed line Bloch band theory, dwelling Brillouin zone. Here, nonunitary...

Disorder and non-Hermiticity dramatically impact the topological localization properties of a quantum system, giving rise to intriguing states matter. The rich interplay disorder, non-Hermiticity, topology is epitomized by recently proposed non-Hermitian Anderson insulator that hosts plethora exotic phenomena. Here we experimentally simulate using disordered photonic walks, characterize its properties. In particular, focus on competition between induced random skin effect under which all...

Non-Hermiticity significantly enriches the properties of topological models, leading to exotic features such as non-Hermitian skin effects and non-Bloch bulk-boundary correspondence that have no counterparts in Hermitian settings. Its impact is particularly illustrating quasicrystals where interplay between non-Hermiticity quasiperiodicity results concurrence delocalization-localization transition, parity-time (PT)-symmetry breaking, onset effects. Here, we experimentally simulate using...

Topology in quench dynamics gives rise to intriguing dynamic topological phenomena, which are intimately connected the topology of static Hamiltonians yet challenging probe experimentally. Here we theoretically characterize and experimentally detect momentum-time skyrmions parity-time [Formula: see text]-symmetric non-unitary single-photon discrete-time quantum walks. The emergent skyrmion structures protected by Chern numbers defined for two-dimensional submanifolds, revealed through our...

The impacts of a model globular protein (bovine serum albumin, BSA) on aggregation kinetics graphene oxide (GO) in aquatic environment were investigated through time-resolved dynamic light scattering at pH 5.5. Aggregation GO without BSA as function electrolyte concentrations (NaCl, MgCl2, and CaCl2) followed the traditional Derjaguin–Landau–Verwey–Overbeek (DLVO) theory, critical coagulation concentration (CCC) was 190, 5.41, 1.61 mM, respectively. As present, it affected stability...

Quantum metrology overcomes standard precision limits and plays a central role in science technology. Practically, it is vulnerable to imperfections such as decoherence. Here we demonstrate quantum for noisy channels that entanglement with ancillary qubits enhances the Fisher information phase estimation but not otherwise. Our photonic experiment covers range of noise various types channels, including two randomly alternating assisted fails each channel individually. We simulate by...

We experimentally simulate in a photonic setting non-Hermitian (NH) metals characterized by the topological properties of their nodal band structures. Implementing nonunitary time evolution reciprocal space followed interferometric measurements, we probe complex eigenenergies corresponding NH Bloch Hamiltonians, and study detail topology exceptional lines (ELs), counterpart Hermitian systems. focus on two distinct types metals: two-dimensional systems with symmetry-protected ELs,...

Non-Bloch topological invariants preserve the bulk-boundary correspondence in non-Hermitian systems, and are a key concept contemporary study of topology. Here we report dynamic detection non-Bloch single-photon quantum walks, revealed through biorthogonal chiral displacement, crosschecked with spin textures generalized quasimomentum-time domain following quench. Both schemes robust against symmetry-preserving disorders, yield consistent results theoretical predictions. Our experiments...

The authors employ single photons and linear optics to simulate a two-qubit quantum battery investigate the relationship between performance of batteries amount entanglement coherence that arise during charging process. results show is not always most important resource boost charging, while plays nontrivial role.

The Heisenberg-Robertson uncertainty relation quantitatively expresses the impossibility of jointly sharp preparation incompatible observables. However it does not capture concept observables because can be trivial even for two We experimentally demonstrate new stronger relations proposed by Maccone and Pati [Phys. Rev. Lett. 113, 260401 (2014)] relating on that sum variances are valid in a state-dependent manner lower bound is guaranteed to nontrivial being state system measured. behaviour...

PageRank is an algorithm used by Google Search to rank web pages in their search engine results. An important step for quantum networks quantize the classical protocol as mechanics provides computational resources that can be outperform algorithms. In this paper, we experimentally realize continuous-time walks directed graphs with non-Hermitian adjacency matrices using linear optical circuits and single photons. We find node centrality a graph correlated maximum probability resulting from...

We propose a novel algorithm for quantum spatial search on star graph using interleaved continuous-time walks and marking oracle queries. Initializing the system in star's central vertex, we determine optimal walk times to reach full overlap with marked state ⌈(π/4)sqrt[N]-(1/2)⌉ queries, matching well-known lower bound of Grover's search. implement deterministic database size seven photonic hardware, demonstrate effective scaling approach up 115. This is first experimental demonstration...

Exceptional points (EPs) of non-Hermitian (NH) systems have recently attracted increasing attention due to their rich phenomenology and intriguing applications. Compared the predominantly studied second-order EPs, higher-order EPs been assumed play a much less prominent role because they generically require tuning more parameters. Here, we experimentally simulate two-dimensional topological NH band structures using single-photon interferometry, observe topologically stable third-order...

As branch-point singularities of non-Hermitian matrices, the exceptional points (EPs) exhibit unique spectral topology and criticality, with intriguing dynamic consequences in settings. In open quantum systems, EPs also emerge Liouvillian spectrum, but their impact often pertains to transient dynamics is challenging demonstrate. Here, using flexible control afforded by single-photon interferometry, we study chiral state transfer when EP parametrically encircled. Reconstructing density-matrix...

Tinnitus is the perception of sounds without any corresponding external stimulus exists, and it one most common hearing disorders. Currently, there are no objective tests for tinnitus, thus its detection relies on subjective reports patients. Here, we introduce a novel three-alternative forced-choice method (3AFC) tinnitus pitch loudness matching. Then, modulate soothing music by increasing sound intensity two 1/3 octave bands above below frequency according to specific algorithm generate...