Research

This page organises my research into a set of themes and links to representative publications on each topic.
For a complete list, please visit my Google Scholar page.

Selected Publications

A. Fualt Tolerant Quantum Computing (FTQC) and Networking

1. Quantum Error Correction (QEC)

Quantum error correction (QEC) is a foundational technique that enables reliable quantum computation by protecting fragile quantum information from noise and decoherence through the use of redundant encoding across multiple physical qubits. It is essential for fault-tolerant quantum computing, as it allows logical qubits to maintain coherence long enough to execute deep quantum circuits, making large-scale and practically useful quantum algorithms feasible.

Focus and contributions

  • Structure-driven design of quantum LDPC and topological codes from classical algebraic, coding-theoretic perspective.
  • Noise- and structure-aware decoding algorithms for quantum codes including bias-aware, degeneracy-exploiting, and single-/few-shot decoders.
  • Noise- and hardware-tailored quantum error-correcting architectures for biased-noise, and Floquet codes, integrating code design with realistic device and noise models.
  • Code-structure–enabled fault-tolerant quantum computation leveraging code strucutre to realize native logical gates and scalable magic-state factories (e.g., CCZ “fountains”).

Representative work

2. Quantum Algorithms for the Fault-Tolerant Era

Fault-tolerant quantum computing enables the execution of deep quantum circuits required for practical applications such as chemistry, materials science, and physics. Among these, Hamiltonian Simulation is a foundational primitive, underlying many higher-level algorithms including phase estimation and quantum linear algebra.

Focus and contributions

  • Optimizing T-count and T-depth via circuit synthesis and algorithmic reformulation
  • Co-designing algorithms with underlying QEC schemes to reduce decoding and communication overhead

Representative work

  • M. Rowshan, “Error Propagation in Quantum Signal Processing Circuits: Noise Analysis and Robust Phase Design,” submitted to IEEE Journal of Selected Topics in Signal Processing, April, 2026.
  • M. Rowshan, “Architecting Fault-Tolerant Quantum Signal Processing: Analytical Foundations, Fidelity Transitions, and Efficient Synthesis,” submitted to IEEE Journal of Selected Topics in Signal Processing, April, 2026.

3. Distributed Networked Fault-Tolerant Quantum Computing (FTQC)

Distributed Networked Fault-Tolerant Quantum Computing (FTQC) systems are architectures in which scalable quantum computation is achieved by interconnecting multiple error-corrected quantum modules through classical and optical networks.

Focus and contributions

  • Latency-sensitive iterative decoding across racks
  • Congestion and bandwidth limitations in top-of-rack and aggregation switches
  • Heterogeneous link reliability, especially lossy inter-rack optical connections

Representative work

  • M. Rowshan, “Network-Coded Syndrome Distribution for Topological QEC,” to be submitted to IEEE Networking Letters, April, 2026.

B. Error Correction Codes for Communications Systems

1. Channel Coding - Polar and PAC Codes: Structure, Algebra, and Weight Distribution

Focus and contributions

  • Algebraic and combinatorial structure of polar and PAC codes (monomial / group-action viewpoint).
  • Exact and partial weight enumerators, with emphasis on minimum- and low-weight codewords.
  • Weight-based partial orders and their use in code design and performance prediction.

Representative publications

2. Channel Coding - Construction of (Pretransformed) Polar Codes

Focus and contributions

  • Design of polar codes that explicitly incorporate weight distribution into the construction.
  • Hybrid reliability–weight constructions (e.g., “retransform” polar codes) that go beyond standard Bhattacharyya-parameter–based designs.
  • Bridging algebraic weight results with practical finite-length code design.

Representative publications

Focus and contributions

  • Low-complexity decoding of polar and PAC codes beyond standard SC and SCL schemes.
  • GRAND-based decoders with segmentation, constrained error pattern generation, and improved complexity–performance trade-offs.
  • Sequential, list, and Fano-type decoders, including partial rewind and shifted-pruning strategies.
  • Connections between code structure (e.g., weight distribution) and decoder behaviour.

Representative publications

4. Channel Coding for 5G, 6G, and Beyond

Focus and contributions

  • System-level viewpoint on channel coding for 5G/6G: requirements, performance targets, and implementation constraints.
  • Comparative assessment and evolution of LDPC, turbo/convolutional, polar/PAC, and related codes in standards.

Representative publications

C. Intersection of Communications Systems and Other Fields

1. Signal Processing for Wireless Communications

Focus and contributions

  • Delay–Doppler channel estimation tailored to modern OFDM and multicarrier systems.
  • Use of ambiguity functions and structured delay–Doppler representations to improve estimation accuracy and robustness.
  • Impact of channel estimation on end-to-end coded performance.

Representative publications

2. VLSI and Hardware–Software Co-Design for Communication Systems

Focus and contributions

  • Quantisation strategies for belief-propagation and list decoders, targeting hardware efficiency.
  • Architectural design for BP decoding of polar codes with non-uniform quantisation.
  • Low-complexity detection algorithms for OTFS modulation

Representative publications

3. Machine Learning in Channel Coding and Communication Systems

Focus and contributions

  • Ongoing research on machine-learning–assisted decoding (e.g., learned heuristics for GRAND or SCL variants).
  • Data-driven design of channel estimation and detection algorithms.

Books

  • M. Rowshan and E. Viterbo, Polar Codes: From Theory to Practice, Hoboken, NJ, USA: Wiley–IEEE Press, 2025, ISBN 978-1-119-91173-9.
  • M. Rowshan and V.-F. Dragoi, The Algebra of Polar Codes: Partial Orders, Automorphisms, Weight Structures, and Applications, Hoboken, NJ, USA: Wiley–IEEE Press, 2027.

Patents

  • H. P. H. Shaw, J. Yuan and M. Rowshan, “Delay-Doppler based channel estimation method and apparatus,” Australian Patent 2024900503, Feb. 28, 2024.