Publications

2025

• “Feynman path integrals for discrete-variable systems: Walks on Hamiltonian graphs” by A. Kalev, and I. Hen, Phys. Rev. Research 7, 013220 (2025). arXiv:2407.11231.

2024

• “Exact and universal quantum Monte Carlo estimators for energy susceptibility and fidelity susceptibility” N. Ezzell, L. Barash and I. Hen, “ Submitted for publication. arXiv:2408.03924 (2024).
• “A simple quantum simulation algorithm with near-optimal precision scaling” by A. Kalev, and I. Hen, submitted for publication. arXiv:2412.10667 (2024).
• “A quantum Monte Carlo algorithm for arbitrary spin-1/2 Hamiltonians” by L. Barash, Arman Babakhani and Itay Hen, Phys. Rev. Research 6, 013281 (2024). arXiv:2307.06503.
• “A quantum Monte Carlo algorithm for Bose-Hubbard models on arbitrary graphs” by Emre Akaturk and Itay Hen, Phys. Rev. B 109, 134519 (2024). arXiv:2309.05166.
• “Accounting for gauge symmetries in CHSH experiments” by David Oaknin, Amir Kalev and Itay Hen, submitted for publication (2024). arXiv:2403.07935.

2023

• “A quantum Monte Carlo algorithm for arbitrary spin-1/2 Hamiltonians” by L. Barash, A. Babakhani and I. Hen, arXiv:2307.06503 (2023).
• “Experimental Demonstration of Quantum Spectrum Estimation by Time-Correlation Measurements” by K. J. Ferris, Z. Wang, N. T. Bronn, I. Hen, A. Kalev and V. Vlček, submitted for publication, arXiv:2312.00687 (2023).

2022

• M. Kowalsky, T. Albash, I. Hen and D. A. Lidar, “3-Regular 3-XORSAT Planted Solutions Benchmark of Classical and Quantum Heuristic Optimizers”, Quantum Sci. Technol. 7 025008 (2022).
• L. Barash, S. Güttel and I. Hen, “Calculating elements of matrix functions using divided differences”, Computer Physics Communications 271, 108219 (2022).
• J. L. C. da C. Filho, Z. G. Izquierdo, A. Saguia, T. Albash, I. Hen, and M. S. Sarandy, “Localization transition induced by programmable disorder“, Phys. Rev. B. 105, 134201 (2022).

2021

• G. Quiroz, P. Titum, P. Lotshaw, P. Lougovski, K. Schultz, E. Dumitrescu and I. Hen, “Quantifying the Impact of Precision Errors on Quantum Approximate Optimization Algorithms”. arXiv:2109.04482 (2021). 
• Y.-H. Chen, A. Kalev, and I. Hen, “A quantum algorithm for time-dependent Hamiltonian simulation by permutation expansion”, PRX Quantum 2, 030342 (2021).
• A. Kalev, and I. Hen, “An integral-free representation of the Dyson series using divided differences”, New J. Phys. 23, 103035 (2021).
• Z. Gonzalez Izquierdo, T. Albash and I. Hen, “Testing a quantum annealer as a quantum thermal sampler”, ACM Transactions on Quantum Computing 2/7, 1-20 (2021).
• I. Hen, “Determining quantum Monte Carlo simulability with geometric phases”, Physical Review Research 3, 023080 (2021).

2020

• T. Halverson, L. Gupta, M. Goldstein and I. Hen, “Efficient simulation of so- called non-stoquastic superconducting flux circuits”, submitted for publication. arXiv:2011.03831 (2020).
• A. Kalev, and I. Hen, “Quantum Algorithm for Simulating Hamiltonian Dynamics with an Off-diagonal Series Expansion”, Quantum 5, 426 (2021). arXiv:2006.02539 (2020).
• E. Crosson, T. Albash, I. Hen, and A. P. Young, “De-Signing Hamiltonians for Quantum Adiabatic Optimization”, Quantum 4, 334 (2020). arXiv:2004.07681.
• Z. Gonzalez Izquierdo, R. Zhou, K. Markstro ̈m and I. Hen, “Discriminating Non- Isomorphic Graphs with an Experimental Quantum Annealer”, Phys. Rev. A 102, 032622. arXiv:2003.00361 (2020).
• L. Gupta, T. Albash and I. Hen, “Permutation Matrix Representation Quantum Monte Carlo”, J. Stat. Mech. 073105 (2020). arXiv:1908.03740.
• J. Klassen, M. Marvian, S. Piddock, M. Ioannou, I. Hen and B. Terhal, “Hardness and Ease of Curing the Sign Problem for Two-Local Qubit Hamiltonians”, SIAM J. Comput., 49(6), 13321362 (2020). arXiv:1906.08800.

2019

• L. Gupta, L. Barash and I. Hen, “Calculating the divided differences of the expo- nential function by addition and removal of inputs”, Computer Physics Commu- nications 254, 107385 (2020). arXiv:1912.12157 (2019).
• L. Gupta and I. Hen, “Elucidating the interplay between non-stoquasticity and the sign problem”, Advanced Quantum Technologies. arXiv:1910.13867 (2019).
• A. Pearson, A. Mishra, I. Hen and D. Lidar, “Analog Errors in Quantum Anneal- ing: Doom and Hope”, npj Quantum Information 5, 107 (2019). arXiv:1907.12678 (2019).
• M. Slutskii, T. Albash, L. Barash and I. Hen, “Analog Nature of Quantum Adiabatic Unstructured Search”, New Journal of Physics 21, 113025 (2019). arXiv:1904.04420.
• L. Barash, J. Marshall, M. Weigel and I. Hen, “Estimating the Density of States of Frustrated Spin Systems”, New Journal of Physics 21, 073065 (2019). arXiv:1808.04340.
• I. Hen, “Equation Planting: A Tool for Benchmarking Ising Machines”, Phys. Rev. Applied 12, 011003 (2019). arXiv:1903.10928.
• T. Albash and I. Hen, Future of physical quantum annealers: impediments and hopes, Science and Culture 85 163-170 (2019).
• I. Hen, “How quantum is the speedup in adiabatic unstructured search?”, Quant. Inf. Proc. 18, 162 (2019). arXiv:1811.08302.
• J. Marshall, D. Venturelli, I. Hen and E. G. Rieffel, “The power of pausing: advanc- ing understanding of thermalization in experimental quantum annealers”, Phys. Rev. Applied 11, 044083 (2019). arXiv:1810.05881.
• T. Albash, V. Martin-Mayor and I. Hen, “Analog Errors in Ising Machines”, Quan- tum Science & Technology 4 02LT03 (2019). arXiv:1806.03744.
• I. Hen, “Resolution of the Sign Problem for a Frustrated Triplet of Spins”, Phys. Rev. E 99, 033306 (2019). arXiv:1811.03027.
• M. Marvian, D. A. Lidar and I. Hen, “On the Computational Complexity of Curing Non-Stoquastic Hamiltonians”, Nature Communications 10, 1571 (2019). arXiv:1802.03408.

2018

• Y. Susa, Y. Yamashiro, M. Yamamoto, I. Hen, D. Lidar and H. Nishimori,“Quantum annealing of the p-spin model under inhomogeneous transverse field driving”, Phys. Rev. A 98, 042326 (2018). arXiv:1808.01582
• I. Hen and T. Albash, “Solving Quantum Spin Glasses with Off-Diagonal Expan- sion Quantum Monte Carlo”, Journal of Physics: Conference Series (JPCS) 1136, 012007 (2018).
• I. Hen, “Off-Diagonal Series Expansion for Quantum Partition Functions”, J. Stat. Mech 053102 (2018). arXiv:1802.08333.

2017

• B. Zhang, G. Wagenbreth, V. Martin-Mayor and I. Hen, “Advantages of unfair quantum ground-state sampling”, Scientific Reports 7, 1044 (2017). arXiv:1701.01524.
• I. Hen, “Realizable quantum adiabatic search”, Europhysics Letters 118, 30003 (2017). arXiv:1612.06012.
• I. Hen, “Solving spin glasses with optimized trees of clustered spins”, Phys. Rev. E 96, 022105 (2017). arXiv:1705.02075.
• T. Albash, V. Martin-Mayor and I. Hen, “Temperature scaling law for quantum annealing optimizers”, Phys. Rev. Lett. 119, 110502 (2017), arXiv:1703.03871.
• J. Marshall, E. Rieffel and I. Hen, “Thermalization, freeze-out and noise: deci- phering experimental quantum annealers”, Phys. Rev. Applied 8, 064025 (2017). arXiv:1703.03902.
• T. Albash, G. Wagenbreth and I. Hen, “Off-diagonal expansion quantum Monte Carlo”. Phys. Rev. E 96, 063309 (2017). arXiv:1701.01499.

2016

• I. Hen and F. M. Spedalieri, “Quantum annealing for constrained optimization”, Phys. Rev. Applied 5, 034007 (2016). arXiv:1508.04212.
• I. Hen and M. S. Sarandy, “Driver Hamiltonians for constrained optimization in quantum annealing”, Phys. Rev. A 93, 062312 (2016). arXiv:1602.07942.
• J. Marshall, V. Martin-Mayor and I. Hen, “Practical Engineering of Hard Spin- Glass Instances”, Phys. Rev. A 94, 012320 (2016). arXiv:1605.03607.
• I. B. Coulamy, A. C. Santos, I. Hen and M. S. Sarandy, “Energetic cost of supera- diabatic quantum computation”, Frontiers in ICT 3, 19 (2016). arXiv:1603.07778.

2015

• I. Hen and A. P. Young, “Performance of the quantum adiabatic algorithm on con- straint satisfaction and spin glass problems”, European Physical Journal Special Topics 224, 63-73 (2015).
• I. Hen, “Quantum gates with controlled adiabatic evolutions”, Phys. Rev. A 91,022309 (2015). arXiv:1401.5172.
• A. Kalev and I. Hen, “Fidelity-optimized quantum state estimation”, New Journal of Physics 17 092008 (2015). arXiv:1409.1952.
• I. Hen and A. P. Young, “Numerical Studies of the Quantum Adiabatic Algorithm, and spin glass problems”, Proceedings of CCP2014, J. Phys.: Conf. Ser. 640,012038 (2015).
• V. Martin-Mayor and I. Hen, “Unraveling Quantum Annealers using Classical Hardness”, Scientific Reports 5, 15324 (2015). arXiv:1502.02494.
• I. Hen, J. Job, T. Albash, Troels F. Roennow, M. Troyer, D. A. Lidar, “Probing for quantum speedup in spin glass problems with planted solutions”, Phys. Rev.A 92, 042325 (2015). arXiv:1502.01663.
• W. Vinci, T. Albash, G. Paz-Silva, I. Hen and D. A. Lidar, “Quantum annealing correction with minor embedding”, Phys. Rev. A 92, 042310 (2015). arXiv:1507.02658.
• T. Albash, I. Hen, F. M. Spedalieri and D. A. Lidar, “Reexamination of the evidence for entanglement in the D-Wave processor”, Phys. Rev. A 92, 062328 (2015). arXiv:1506.03539.

2014

• I. Hen, “How Fast Can Quantum Annealers Count?”, J. Phys. A: Math. Theor.47, 235304 (2014). arXiv:1301.4956.
• I. Hen, “Continuous-Time Quantum Algorithms for Unstructured Problems”, J.Phys. A: Math. Theor. 47, 045305 (2014). arXiv:1302.7256
• I. Hen, “Period finding with Adiabatic Quantum Computation”, Europhysics Letters 105, 50005 (2014). arXiv:1307.6538.
• E. G. Rieffel, M. Do, D. Venturelli, I. Hen and J. Franks, “Phase Transitions in Planning Problems: Design and Analysis of Parameterized Families of Hard Planning Problems”, AAAI 2014: 2337-2343 (2014).

Older Papers

• I. Hen, “Fourier-transforming with quantum annealers”. Front. Phys. 2, 44 (2014).
• I. Hen, “Excitation Gap from Optimized Correlation Functions in Quantum Monte Carlo Simulations”, Phys. Rev. E 85, 036705 (2012). arXiv:1112.2269.
• I. Hen and A. P. Young, “Solving the Graph Isomorphism Problem with a Quantum Annealer”, Phys. Rev. A 86, 042310 (2012). arXiv:1207.1712.
• E. Farhi, D. Gosset, I. Hen, A. W. Sandvik, P. Shor, A. P. Young, and F. Zamponi, “The performance of the quantum adiabatic algorithm on 3 Regular 3XORSAT and 3 Regular Max-Cut”, Phys. Rev. A 86, 052334 (2012). arXiv:1208.3757.
• l. Hen and A. P. Young, “Exponential Complexity of the Quantum Adiabatic Algorithm for certain Satisfiability Problems”, Phys. Rev. E 84, 061152 (2011). arXiv:1109.6872.
• I. Hen and M. Rigol, “Strongly interacting atom lasers in three dimensional optical lattices”, Phys. Rev. Lett. 105, 180401 (2010). arXiv:1010.5553.
• I. Hen and M. Rigol, “Analytical and numerical study of trapped strongly correlated bosons in two- and three-dimensional lattices”, Phys. Rev. A 82, 043634 (2010). arXiv:1005.1915.
• I. Hen, M. Iskin and M. Rigol, “Phase diagram of the hardcore Bose-Hubbardmodel on a checkerboard superlattice”, Phys. Rev. B 81, 064503 (2010). arXiv:0911.0890.
• F. Alexander Wolf, I. Hen and M. Rigol, “Collapse and revival oscillations as a probe for the tunneling amplitude in an ultracold Bose gas”, Phys. Rev. A 82, 043601 (2010). arXiv:1010.1776.
• I. Hen and M. Karliner, “Review of rotational symmetry breaking in baby Skyrme models”, in G. Brown and M. Rho, Eds., The Multifaceted Skyrmion, (World Scientific, Singapore, 2010).
• I. Hen and M. Rigol, “Superfluid to Mott-insulator transition of hardcore bosons in a superlattice”, Phys. Rev. B 80, 134508 (2009). arXiv:0905.4920.
• I. Hen and M. Karliner, “Lattice structure of baby skyrmions”, Theoretical and Mathematical Physics 160(1), 934 (2009).
• I. Hen and A. Kalev, “Equations of motion for the quantum characteristic func- tions”, arXiv:0803.0108 (2008).
• I. Hen and M. Karliner, “Rotational symmetry breaking in baby Skyrme models”, Nonlinearity 21, 399 (2008). arXiv:0901.1489.
• A. Kalev and I. Hen, “No-broadcasting theorem and its classical counterpart”, Phys. Rev. Lett. 100, 210502 (2008). arXiv:0704.1754.
• I. Hen and M. Karliner, “Spontaneous breaking of rotational symmetry in rotating solitons: a toy model of excited nucleons with high angular momentum”, Phys. Rev. D 77, 116002 (2008). arXiv:0802.2348.
• I. Hen and M. Karliner, “Baby skyrmions on the two-sphere”, Phys. Rev. E 77, 036612 (2008). arXiv:0711.1974.
• I. Hen and M. Karliner, “Hexagonal structure of baby skyrmion lattices”, Phys. Rev. D 77, 054009 (2008). arXiv:0711.2387.
• I. Hen and A. Kalev, “Classical states and their quantum correspondence”, arXiv:quant- ph/0701015 (2007).
• H. Braunstein-Bercovitz, I. Hen and R. E. Lubow, “Masking task load modulates latent inhibition”, Cognition and Emotion 18, 1135 (2004).
• I. Hen, A. Sakov, N. Kafkafi, I. Golani and Y. Benjamini, “The dynamics of spatial behavior: how can robust smoothing techniques help?”, Journal of Neuroscience Methods 133, 161 (2004).