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Drought and extreme heat do not always occur separately. When they coincide, their combined effects can place greater pressure on water resources, agriculture, ecosystems, energy systems and public health.
Phys.org ResearchRead article →Fires in the U.S. are getting faster, larger and more dangerous, but people continue to develop and move into fire-prone regions. New research from the University of Colorado Boulder's Cooperative Institute for Research in Environmental Sciences (CIRES) shows that if we don't act on climate change, which fuels fires, manage vegetation or transform how we build and adapt to fire, the risk to structures in the U.S.
Phys.org ResearchRead article →arXiv:2611.01180v1 Announce Type: new Abstract: We show that encoding superconducting qubits as dual-rail or spin-locked transmons lets a metamaterial waveguide couple them all-to-all while suppressing the spurious entanglement that burdens shared-mode architectures, a step toward the non-local connectivity that quantum low-density parity-check codes require.
arXiv QuantumRead article →arXiv:2611.01163v1 Announce Type: new Abstract: We study the problem of estimating the quantum divergence with $p$-power means, $\Phi_p(\rho\,\|\,\sigma)$. This quantity was investigated by Lam and Le (\textit{Linear Algebra Appl.}\ 2021).
arXiv QuantumRead article →arXiv:2611.01079v1 Announce Type: new Abstract: Accurate measurement of reduced density matrices (RDMs) is central to quantum simulations of many-fermion systems, but the required measurement resources remain a significant challenge. Constrained shadow tomography (CST) combines randomized measurements with $N$-representability conditions to reconstruct physically valid RDMs from limited measurement data.
arXiv QuantumRead article →arXiv:2611.01027v1 Announce Type: new Abstract: We develop a conic-programming framework for multiparameter estimation of quantum processes under different classes of sensing strategies. Estimation precision depends on the choice of input probe state and measurement and, when a channel is used multiple times, on the arrangement of channel uses and intermediate controls.
arXiv QuantumRead article →arXiv:2611.00985v1 Announce Type: new Abstract: We develop normal factor graph (NFG) representations of stabilizer quantum error-correcting codes and entanglement-assisted quantum error-correcting codes. We introduce two complementary representations.
arXiv QuantumRead article →arXiv:2611.00934v1 Announce Type: new Abstract: Single-mode squeezing of the electromagnetic vacuum is a key resource for mode-selective noise reduction in quantum measurements. At microwave frequencies, single-mode squeezing is typically obtained by using Josephson and Traveling-Wave Parametric Amplifiers designed for three-wave mixing operation.
arXiv QuantumRead article →arXiv:2611.00931v1 Announce Type: new Abstract: We characterize the exact error-exponent trade-off in binary quantum hypothesis testing with a rejection option for faithful states on a finite-dimensional Hilbert space. The probabilities of rejection under the two hypotheses are required to vanish exponentially, with exponents at least $K$ and $L$.
arXiv QuantumRead article →arXiv:2611.00902v1 Announce Type: new Abstract: We study a symmetry-restoration quantum Mpemba effect in the dissipative Dicke model as an example of a weakly $\mathbb Z_2$-symmetric open quantum system, where the full Liouvillian is parity covariant although individual quantum jumps connect the two Hilbert-space parity sectors.
arXiv QuantumRead article →arXiv:2611.00885v1 Announce Type: new Abstract: When a variational quantum classifier performs poorly at detecting network attacks, it is hard to tell which part is to blame: the encoding, the trained circuit or the readout, which turns measurements into a class.
arXiv QuantumRead article →arXiv:2611.00878v1 Announce Type: new Abstract: Quantum batteries promise faster and more efficient energy storage and extraction by harnessing quantum mechanics, serving as essential building blocks for future quantum devices. A key practical requirement-unidirectional energy flow during charging-is straightforward in classical batteries via potential difference, yet remains a major challenge in the quantum regime…
arXiv QuantumRead article →arXiv:2611.00874v1 Announce Type: new Abstract: Correction-free teleportation protocols offer a probabilistic route around the limits imposed by the quantum no-programming theorem, but have remained largely theoretical. Here, we experimentally implement and benchmark correction-free multicopy teleportation on noisy superconducting quantum hardware.
arXiv QuantumRead article →arXiv:2611.00832v1 Announce Type: new Abstract: A Gaussian position distribution need not imply that frozen disorder is irrelevant. We study a resonant quantum chain where neighboring sites couple with opposite signs to auxiliary states that decay with frozen, random return probabilities. Lowering dephasing spreads the effect of each local return bias over more sites.
arXiv QuantumRead article →arXiv:2611.00759v1 Announce Type: new Abstract: Constrained quantum samplers often produce infeasible outputs that retain information about good feasible solutions. We develop a post-measurement framework that constructs problem-dependent classical feasibility maps from constraint-violation statistics and pushes the raw quantum sampling law forward onto the feasible set.
arXiv QuantumRead article →arXiv:2611.00751v1 Announce Type: new Abstract: Weakly correlated electronic structures are predominant among molecules, and are routinely solved with heuristic classical methods such as the ``gold standard'' CCSD(T) coupled cluster model, incurring a formal time complexity $O(n^7)$ in the number of molecular orbitals and with no guarantee of energy error $\varepsilon$ at or below chemical accuracy.
arXiv QuantumRead article →arXiv:2611.00694v1 Announce Type: new Abstract: Photon loss somewhat limits fault-tolerant photonic quantum computing. We investigate its effect on finite-energy Gottesman--Kitaev--Preskill (GKP) states by modeling the pure-loss channel directly.
arXiv QuantumRead article →arXiv:2611.00678v1 Announce Type: new Abstract: Iterative quantum optimization (IQO) uses quantum-generated information to select a sequence of classical problem reductions. We introduce Bound-Aware Tree-IQO which combines this iterative structure with bounds and reversible search. Feasible measured samples update a shared incumbent, while valid classical bounds prune branches that cannot improve it.
arXiv QuantumRead article →arXiv:2611.00620v1 Announce Type: new Abstract: A central obstacle in realizing color center cavity-QED-based quantum technologies is inhomogeneity, or disorder, among individual emitters. As the number of emitters increases, so does the complexity of the experimental data, making it difficult to quantify the present physical mechanisms of disorder.
arXiv QuantumRead article →arXiv:2611.00609v1 Announce Type: new Abstract: Given a quantum adversary that queries a random oracle, how do we characterize the information that they "know"? The Compressed Oracle method of Zhandry (CRYPTO 2019) is one method that records the queries that the adversary makes; this recording serves as a representation of the information that is learned.
arXiv QuantumRead article →arXiv:2611.00603v1 Announce Type: new Abstract: Positive-definite neural-network quantum states cannot directly represent the ground state of the PXP Hamiltonian, since the ground-state wavefunction carries a nontrivial relative-sign structure.
arXiv QuantumRead article →arXiv:2611.00601v1 Announce Type: new Abstract: In realistic quantum systems, isolated few-level models usually provide only an approximate description, since the controlled subsystem is generally coupled to additional degrees of freedom. As a result, a quantum control scheme designed for an isolated system may lose its original performance in a more complex coupled setting.
arXiv QuantumRead article →arXiv:2611.00599v1 Announce Type: new Abstract: Randomized measurements provide state-independent readout for multiparameter quantum sensing. Although 3-designs retain a constant fraction of the quantum Fisher information (QFI) for every pure state, we show that 2-designs need not.
arXiv QuantumRead article →arXiv:2611.00573v1 Announce Type: new Abstract: Optimizing parameters separately for each problem instance limits the reuse of variational quantum algorithms. We develop empirical scaling laws for parameter setting in the digitized counterdiabatic quantum approximate optimization algorithm (DC-QAOA) for weighted MaxCut.
arXiv QuantumRead article →