Publications in Refereed Papers and Talks

• T. Fujii and M. Hirokawa,
  On Performance of Concealing-Restoring System for Analog Signals on Physical Layer,
  International Conference on Electrical, Computer and Energy Technologies (ICECET2022), Prague, Czech Republic, 20-22 Jul., 2022.
  The paper is in the IEEE Xplore.
  Scopus Citation Index & FWCI.
• M. Hirokawa,
  On Accuracy of Restoration of Concealing-Restoring System for Physical Layer,
  International Conference on Electrical, Computer and Energy Technologies (ICECET2021), Cape Town, South Africa, 09-10 Dec., 2021.
  The paper is in the IEEE Xplore.
  Scopus Citation Index & FWCI.
• T. Fujii and M. Hirokawa,
  Concealing-Restoring System for Physical Layer Data: Based on Stochastic Filtering Theory,
  Physical Communication 52: 101602 (21 pages), 2022.
  Scopus Citation Index & FWCI.
• T. Fujii and M. Hirokawa,
  A Data Concealing Technique with Random Noise Disturbance and A Restoring Technique for the Concealed Data by Stochastic Process Estimation,
  Mathematics for Industry 33: 103-124, 2021.
• M. Hirokawa,
  Schrödinger-Cat-Like States with Dressed Photons in Renormalized Adiabatic Approximation for Generalized Quantum Rabi Hamiltonian with Quadratic Interaction,
  Physics Open 5: 100039, 2020.
  Scopus Citation Index & FWCI.
• T. Tanimoto, S. Matsuo, S. Kawakami, Y. Tabuchi, M. Hirokawa, and K. Inoue,
  Practical Error Modeling Toward Realistic NISQ Simulation,
  the 1st International Workshop on Quantum Computing: Circuits Systems Automation and Applications (QC-CSAA) in conjunction with the ISVLSI 2020, pp. 291-293, July 2020.
  Scopus Citation Index & FWCI.
• T. Tanimoto, S. Matsuo, S. Kawakami, Y. Tabuchi, M. Hirokawa, and K. Inoue,
  How Many Trials Do We Need for Reliable NISQ Computing?,
  the 1st International Workshop on Quantum Computing: Circuits Systems Automation and Applications (QC-CSAA) in conjunction with the ISVLSI 2020, pp. 288-290, July 2020.
  Scopus Citation Index & FWCI.
• M. Ichimura and M. Hirokawa,
  Topological Superconductors in Ferromagnetic Nanowires with Domain Wall,
  a poster presentation at the 14th Joint MMM-Intermag Conference, LLC and the IEEE Magnetics Society (Jan. 14-18, 2019, Washington, DC)
• M. Hirokawa,
  A mathematical modeling of electron-phonon interaction for small wave numbers close to zero,
  in the book edited by J. Dittrich, H. Kovarik, A. Laptev (Eds.): p.373-p.400
  EMS Series of Congress Reports Functional Analysis and Operator Theory for Quantum Physics.
  Pavel Exner Anniversary Volume (Europ. Math. Soc. Publ. House, 2017).
• M. Hirokawa, J. Møller and I. Sasaki,
  A Mathematical Analysis of Dressed Photon in Ground State of Generalized Quantum Rabi Model Using Pair Theory,
  Journal of Physics A: Mathematical and Theoretical 50(18): 184003, 2017.
  Scopus Citation Index & FWCI.
• M. Hirokawa,
  Duality between A Dark State And A Quasi-Dark State,
  Annals of Physics (N.Y.) 377: 229-242, 2017.
  Scopus Citation Index & FWCI.
• M. Hirokawa,
  The Rabi model gives off a flavor of spontaneous SUSY breaking,
  Quantum Studies: Mathematics and Foundations 2(4): 379-388, 2015.
  Scopus Citation Index & FWCI.
• M. Hirokawa and F. Hiroshima,
  Absence of energy level crossing for the ground state energy of the Rabi model,
  Communications on Stochastic Analysis 8(4): 551-560, 2014.
• M. Hirokawa, F. Hiroshima, and J. Lorinczi,
  Spin-Boson Model through a Poisson-Driven Stochastic Process,
  Mathematische Zeitschrift 277(3-4): 1165-1198, 2014.
  Scopus Citation Index & FWCI.
• M. Hirokawa and T. Kosaka,
  A Mathematical Aspect of A Tunnel-Junction for Spintronic Qubit,
  Journal of Mathematical Analysis and Applications 417(2): 856-872, 2014.
  Scopus Citation Index & FWCI.
• M. Hirokawa and T. Kosaka,
  One-Dimensional Tunnel-Junction Formula for Schrödinger Particle,
  SIAM Journal on Applied Mathematics 73(6): 2247-2261, 2013.
  Scopus Citation Index & FWCI.
• Y. Shikano and M. Hirokawa,
  Boundary Conditions in One-dimensional Tunneling Junction,
  Journal of Physics: Conference Series 302: 0124044, 2011.
  Scopus Citation Index & FWCI.
• Y. Furuhashi, M. Hirokawa, K. Nakahara and Y. Shikano,
  Role of Phase Factor in Boundary Condition of One-Dimensional Junction,
  Journal of Physics A: Mathematical and Theoretical, 43(35): 354010, 2010.
  ( Special issues: Quantum Phases: 50 Years of the Aharonov-Bohm Effect and 25 Years of the Berry Phase ).
  Scopus Citation Index & FWCI.
• M. Hirokawa,
  Dicke-Type Energy Level Crossings in Cavity-Induced Atom Cooling: Another Superradiant Cooling,
  Physical Review A 79(4): 043408, 2009.
  Scopus Citation Index & FWCI.
• M. Hirokawa,
  The Dicke-Type Crossings among Eigenvalues of Differential Operators in A Class of Non-Commutative Oscillator,
  Indiana University Mathematics Journal 58(4):pp.1493--1536, 2009.
  Scopus Citation Index & FWCI.
• A. Arai, M. Hirokawa, and F. Hiroshima
  Regularities of ground states of quantum field models,
  Kyushu Journal of Mathematics 61(2):pp.321--372, 2007.
  Scopus Citation Index & FWCI.
• M. Hirokawa,
  Infrared Catastrophe for Nelson's Model. --- Non-Existence of Ground State and Soft-Boson Divergence ---,
  Publications of RIMS 42(4):pp.897--922, 2006.
  Scopus Citation Index & FWCI.
• C. Hainzl, M. Hirokawa, and H. Spohn,
  Binding Energy for Hydrogen-Like Atoms in the Nelson Model without Cutoffs,
  Journal of Functional Analysis, 220(2):pp.424--459, 2005.
  Scopus Citation Index & FWCI.
• M. Hirokawa, F. Hiroshima and H. Spohn,
  Ground State for Point Particles Interacting Through a Massless Scalar Bose Field,
  Advances in Mathematics 191(2):pp.339--392, 2005.
  Scopus Citation Index & FWCI.
• J. Dittrich, P. Exner, and M. Hirokawa,
  A Model of Interband Radiative Transition,
  Journal of the Mathematical Society of Japan 56(3):pp.753--786, 2004.
  Scopus Citation Index & FWCI.
• M. Hirokawa,
  Recent Developments in Mathematical Methods for Models in Non-Relativistic Quantum Electrodynamics,
  in A Garden of Quanta,
  J. Arafune, A. Arai, M. Kobayashi, K. Nakamura, T. Nakamura, I. Ojima, N. Sakai, A. Tonomura, and K. Watanabe, eds.,
  World Scientific, pp.209--242, 2003.
• M. Hirokawa,
  Ground State Transition for Two-Level System Coupled with Bose Field,
  Physics Letters A 294(1):pp.13--18, 2002.
  Scopus Citation Index & FWCI.
• M. Hirokawa and O. Ogurisu,
  Ground State of a Spin-1/2 Charged Particle in a Two-Dimensional Magnetic Field ,
  Journal of Mathematical Physics 42(8):pp.3334--3343, 2001.
  Scopus Citation Index & FWCI.
• A. Arai and M. Hirokawa,
  Stability of Ground States in Sectors and Its Application to the Wigner-Weisskopf Model,
  Reviews in Mathematical Physics 13(4): pp.513--527, 2001.
  Scopus Citation Index & FWCI.
• M. Hirokawa,
  Remarks on the Ground State Energy of the Spin-Boson Model. An Application of the Wigner-Weisskopf Model,
  Reviews in Mathematical Physics 13(2): pp.221--251, 2001.
  Scopus Citation Index & FWCI.
• A. Arai and M. Hirokawa,
  Ground States of a General Class of Quantum Field Hamiltonians,
  Reviews in Mathematical Physics 12(8): pp.1085--1135, 2000.
  Scopus Citation Index & FWCI.
• M. Hirokawa,
  Canonical Quantization on a Doubly Connected Space and the Aharonov-Bohm Phase,
  Journal of Functional Analysis 174(2): pp.322--363, 2000.
  Scopus Citation Index & FWCI.
• M. Hirokawa,
  On an expression of the ground state energy of the spin-boson Hamiltonian,
  in Mathematical Methods of Quantum Physics,
  C. C. Bernido, M. V. C. Bernido, K. Nakamura and K. Watanabe, eds.,
  Gordon and Breach Science Publishers, pp.99--107, 1999.
• P. Exner, M. Hirokawa, and O. Ogurisu,
  Anomalous Pauli Electron States for Magnetic Fields with Tails,
  Letters in Mathematical Physics 50(2): pp.103--114, 1999.
  Scopus Citation Index & FWCI.
• A. Arai, M. Hirokawa and F. Hiroshima,
  On the Absence of Eigenvectors of Hamiltonians in a Class of Massless Quantum Field Models Without Infrared Cutoff,
  Journal of Functional Analysis 168(2): pp.470--497, 1999.
  Scopus Citation Index & FWCI.
• M. Hirokawa,
  An Expression of the Ground State Energy of the Spin-Boson Model,
  Journal of Functional Analysis 162(1): pp.178--218, 1999.
  Scopus Citation Index & FWCI.
• M. Hirokawa,
  An Inverse Problem in Quantum Field Theory and Canonical Correlation Functions
  ----- An Application of a Solvable Model Called the Rotating Wave Approximation,
  Journal of the Mathematical Society of Japan 51(2):pp.337--369, 1999.
  Scopus Citation Index & FWCI.
• A. Arai and M. Hirokawa,
  On the Existence and Uniqueness of Ground States of a Generalized Spin-Boson Model,
  Journal of Functional Analysis 151(2):pp.455--503, 1997.
  Scopus Citation Index & FWCI.
• M. Hirokawa.
  General Properties between Canonical Correlation and the Independent-Oscillator Model on a Partial *-Algebra,
  Journal of Mathematical Physics 37:pp.121--146, 1996.
  Scopus Citation Index & FWCI.
• M. Hirokawa.
  A Mathematical Relation between the Potential of the Rotating Wave Approximation and an Estimation of the Fluctuation in Mori's Theory,
  Annals of Physics (N.Y.) 234(2):pp.185--210, 1994.
  Scopus Citation Index & FWCI.
• M. Hirokawa,
  Mori's Memory Kernel Equation in Equilibrium Quantum Systems in Finite Volume,
  Annals of Physics (N.Y.) 229(2):pp.354--383, 1994.
  Scopus Citation Index & FWCI.
• Y. Kanada and M. Hirokawa.
  Stochastic problem solving by local computation based on self-organization paradigm,
  ----- the 27th Hawaii International Conference on System Sciences,
  Wailea, Hawaii, January 4-7, 1994
  IEEE Computer Society Press Reprint, pp.82--91, 1994.
  Scopus Citation Index & FWCI.
• M. Hirokawa.
  Mori's Memory Kernel Equation for a Quantum Harmonic Oscillator Coupled to RWA-oscillator,
  Annals of Physics (N.Y.) 224(2):pp.301--341, 1993.
  Scopus Citation Index & FWCI.
• M. Hirokawa,
  Rigorous Construction of Liouville Space and Thermo Field Dynamics for Bosonic Systems in Mathematics,
  Annals of Physics (N.Y.) 223(1):pp.1--36, 1993.
  Scopus Citation Index & FWCI.

 Unsubmitted

• M. Hirokawa,
  Some Remarks on Stability of Formation of Large Bipolaron,
  ( arXiv: cond-mat/0606095, 2006)
• M. Hirokawa and M. Okada,
  Introductory Remarks on Mathematical Relations between Normal Frequency and Zero-Point Fluctuation,
  (preprint, 2001)
• M. Hirokawa,
  Mori's Langevin equation for a quantum harmonic oscillator coupled to infinitely many scalar Bosons,
  (Master Thesis: Hokkaido University Preprint Series in Mathematics, No.49, 1989)