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The Schrodinger cat's Post

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Sharing the latest developments in the world of quantum science. I am not a bot. In the real life, I am Adrien Devolder (@adriendevolder), research associate in quantum control at the University of Toronto.

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The Schrodinger cat's Post @schrodcatpost.bsky.social · Nov 22

Back on Bluesky!
Discover the latest developments in quantum science and technology here!
Every day, we will post a selection of interesting arXiv articles and share significant updates from the industry.
Stay updated of the quantum revolution by following us!

The Schrodinger cat's Post @schrodcatpost.bsky.social · 1d

That’s it for the daily selection. If you enjoyed it, please consider giving me a like or reposting to support my content. Thanks! (Remember that these papers are published on arXiv before undergoing any peer review.)

The Schrodinger cat's Post @schrodcatpost.bsky.social · 1d

A new work develop a filtered-state preparation framework that amplifies the overlap of an initial quantum state with a target eigenstate using spectral filters.

arxiv.org/abs/2510.04294

Filtered Quantum Phase Estimation

Accurate state preparation is a critical bottleneck in many quantum algorithms, particularly those for ground state energy estimation. Even in fault-tolerant quantum computing, preparing a quantum sta...

The Schrodinger cat's Post @schrodcatpost.bsky.social · 1d

A new article proposes a bosonic quantum error-correcting code built from superpositions of squeezed Fock states. This code achieves exact orthogonality and protects against both single-photon loss and dephasing.
arxiv.org/abs/2510.04209

Quantum Error Correction with Superpositions of Squeezed Fock States

Bosonic codes, leveraging infinite-dimensional Hilbert spaces for redundancy, offer great potential for encoding quantum information. However, the realization of a practical continuous-variable bosoni...

The Schrodinger cat's Post @schrodcatpost.bsky.social · 1d

A new study shows that trapped ions can act as self-sensing probes to measure and optimize the laser beams that control them, using the four-photon Stark shift.
arxiv.org/abs/2510.03966

Ion-Based Characterization of Laser Beam Profiles for Quantum Information Processing

Laser-driven operations are a common approach for engineering one- and two-qubit gates in trapped-ion arrays. Measuring key parameters of these lasers, such as beam sizes, intensities, and polarizatio...

The Schrodinger cat's Post @schrodcatpost.bsky.social · 1d

A new work propose H-VEC, a hybrid protocol that turns any classical bit-flip code into a quantum code capable of correcting all Pauli errors, at the expense of more classical sampling.
arxiv.org/abs/2510.05008

Correcting quantum errors using a classical code and one additional qubit

Classical error-correcting codes are powerful but incompatible with quantum noise, which includes both bit-flips and phase-flips. We introduce Hadamard-based Virtual Error Correction (H-VEC), a protoc...

The Schrodinger cat's Post @schrodcatpost.bsky.social · 1d

A new paper shows simulating fermions on qubit-based quantum computers can be done much more efficiently than previously thought using a new way to perform fermionic permutations in the Jordan–Wigner and related encodings.
arxiv.org/abs/2510.05099

Simulating fermions with exponentially lower overhead

Simulating time evolution under fermionic Hamiltonians is a compelling application of quantum computers because it lies at the core of predicting the properties of materials and molecules. Fermions ca...

The Schrodinger cat's Post @schrodcatpost.bsky.social · 1d

Today #quantum article selection:
- Optimized fermion-to-qubit mapping
- QEC using a classical code and one additional qubit
- Calibration of ion processors
- QEC with superposition of squeezed Fock states
- Filtered QPE

More details and links below:

The Schrodinger cat's Post @schrodcatpost.bsky.social · 1d

Nobel Prize in Physics for the works that made superconducting qubits possible!
www.nobelprize.org

The Schrodinger cat's Post @schrodcatpost.bsky.social · 2d

That’s it for the daily selection. If you enjoyed it, please consider giving me a like or reposting to support my content. Thanks! (Remember that these papers are published on arXiv before undergoing any peer review.)

The Schrodinger cat's Post @schrodcatpost.bsky.social · 2d

A new article shows that variational quantum algorithms based on boson sampling can be made much faster and easier to optimize by constraining the phase shifters to have only two distinct eigenvalues. This simple restriction removes local minima and barren plateaus.
arxiv.org/abs/2510.02430

Mitigating the barren plateau problem in linear optics

We demonstrate a significant speedup of variational quantum algorithms that use discrete variable boson sampling when the parametrised phase shifters are constrained to have two distinct eigenvalues. ...

The Schrodinger cat's Post @schrodcatpost.bsky.social · 2d

A new study developed a new variational method called Pauli Path Simulation to efficiently generate circuits that approximate ground states of complex quantum systems. They applied it to models with over 100 qubits, achieving near-exact agreement with classical benchmarks.
arxiv.org/abs/2510.02428

Utility-Scale Quantum State Preparation: Classical Training using Pauli Path Simulation

We use Pauli Path simulation to variationally obtain parametrized circuits for preparing ground states of various quantum many-body Hamiltonians. These include the quantum Ising model in one dimension...

The Schrodinger cat's Post @schrodcatpost.bsky.social · 2d

Spectroscopy tells us how molecules respond to light, but predicting those spectra is classically intractable. A new work presents a universal framework to compute any spectroscopic signal, linear, nonlinear, magnetic, or electric, on a quantum computer.
arxiv.org/abs/2510.02784

Any type of spectroscopy can be efficiently simulated on a quantum computer

Spectroscopy is the most important method for probing the structure of molecules. However, predicting molecular spectra on classical computers is computationally expensive, with the most accurate meth...

The Schrodinger cat's Post @schrodcatpost.bsky.social · 2d

Researchers used quantum sensors to take microscopic magnetic pictures of superconductor under high pressure. They discovered that superconductivity in these materials is patchy and strongly influenced by local stress and composition.
arxiv.org/abs/2510.02429

Uncovering origins of heterogeneous superconductivity in La$_3$Ni$_2$O$_7$ using quantum sensors

The family of nickelate superconductors have long been explored as analogs of the high temperature cuprates. Nonetheless, the recent discovery that certain stoichiometric nickelates superconduct up to...

The Schrodinger cat's Post @schrodcatpost.bsky.social · 2d

A new article formalizes a new "no-go theorem": you can’t have a family of error-correcting codes that is simultaneously efficient (high rate), robust (high distance), and easy to compute with (short logical gate depth).
arxiv.org/abs/2510.03057

Tradeoffs on the volume of fault-tolerant circuits

Dating back to the seminal work of von Neumann [von Neumann, Automata Studies, 1956], it is known that error correcting codes can overcome faulty circuit components to enable robust computation. Choos...

The Schrodinger cat's Post @schrodcatpost.bsky.social · 2d

Today #quantum article selection:
- Tradeoff between rate, distance and accessibility of FT codes
- quantum sensor of superconductivity
- Quantum simulation of spectroscopy
- Quantum state preparation
- Mitigating the barren plateau

More details and links below:

The Schrodinger cat's Post @schrodcatpost.bsky.social · 5d

That’s it for the daily selection. If you enjoyed it, please consider giving me a like or reposting to support my content. Thanks! (Remember that these papers are published on arXiv before undergoing any peer review.)

The Schrodinger cat's Post @schrodcatpost.bsky.social · 5d

Many quantum algorithms require lots of small-angle rotations. A new work directly implement these rotations fault-tolerantly in the surface code.
arxiv.org/abs/2510.01319

A robust phase of continuous transversal gates in quantum stabilizer codes

A quantum error correcting code protects encoded logical information against errors. Transversal gates are a naturally fault-tolerant way to manipulate logical qubits but cannot be universal themselve...

The Schrodinger cat's Post @schrodcatpost.bsky.social · 5d

A new paper systematically studies how algorithmic choices (simulation method, basis set, and encoding scheme) impact the quantum resources needed for QPE in chemistry.
arxiv.org/abs/2510.01710

Benchmarking Quantum Simulation Methods

Quantum Phase Estimation (QPE) is a cornerstone algorithm for fault-tolerant quantum computation, especially for electronic structure calculations of chemical systems. To accommodate the diverse chara...

The Schrodinger cat's Post @schrodcatpost.bsky.social · 5d

A new study propose a new way to boost sensitivity in quantum-sensor-based dark matter searches by projecting multiple sensors into a collective W state.
arxiv.org/abs/2510.01816

Background Suppression in Quantum Sensing of Dark Matter via $W$ State Projection

We show that measuring dark matter signal by projecting quantum sensors in the collective excited state can highly suppress the non-collective noise background, hence improving the sensitivity signifi...

The Schrodinger cat's Post @schrodcatpost.bsky.social · 5d

The author of a new article prove that for Hamiltonians with only an inverse-polynomial energy gap, one can efficiently prepare the ground state using shallow circuits built from Pauli rotations.
arxiv.org/abs/2510.01563

Quantum advantages in ground state preparation, combinatorial optimization, and quantum state preparation

We show that for any quantum Hamiltonian with an inverse-polynomial gap, the ground state can be prepared in a polynomial circuit depth to inverse-polynomial precision, if the system size is sufficien...

The Schrodinger cat's Post @schrodcatpost.bsky.social · 5d

By focusing on Floquet dynamics with large Trotter steps, the simulation of many-body localization crossover can be done on NISQ devices.
arxiv.org/abs/2510.01983

Digital quantum simulation of many-body localization crossover in a disordered kicked Ising model

Simulating nonequilibrium dynamics of quantum many-body systems is one of the most promising applications of quantum computers. However, a faithful digital quantum simulation of the Hamiltonian evolut...

The Schrodinger cat's Post @schrodcatpost.bsky.social · 5d

Today #quantum article selection:
- Quantum simulation of many-body systems
- Quantum advantage for Hamiltonians with an inverse-polynomial gap
- Quantum sensing of dark matter
- Benchmarking quantum simulation
- Continuous transversal gates

More details and links below:

The Schrodinger cat's Post @schrodcatpost.bsky.social · 6d

That’s it for the daily selection. If you enjoyed it, please consider giving me a like or reposting to support my content. Thanks! (Remember that these papers are published on arXiv before undergoing any peer review.)

The Schrodinger cat's Post @schrodcatpost.bsky.social · 6d

A new study explores quantum-classical ML for credit default prediction. They used quantum feature maps to embed financial data and then integrated them into a classical ensemble models, showing modest improvement.
arxiv.org/abs/2510.01129

Credit Default Prediction with Projected Quantum Feature Models and Ensembles

Accurate prediction of future loan defaults is a critical capability for financial institutions that provide lines of credit. For institutions that issue and manage extensive loan volumes, even a slig...

The Schrodinger cat's Post @schrodcatpost.bsky.social · 6d

A new depth-aware circuit optimization framework combines exact synthesis with a scalable heuristic for larger circuits. It supports hardware-aware cost functions (like T-count or entangling-gate minimization), and achieves significant gate/depth reductions in practice.
arxiv.org/abs/2510.00649

Provably Optimal Quantum Circuits with Mixed-Integer Programming

We present a depth-aware optimization framework for quantum circuit compilation that unifies provable optimality with scalable heuristics. For exact synthesis of a target unitary, we formulate a mixed...