Ivan Rojkov

PhD student in the Trapped Ion Quantum Information group. Institute for Quantum Electronics, ETH Zürich, 8093 Zürich, Switzerland.

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I am currently enrolled in a PhD program at ETH Zürich, where I am conducting research under the guidance of Florentin Reiter and Jonathan Home in the theory team of the Trapped Ion Quantum Information group.

My research interests lie at the intersection of theoretical quantum optics and quantum information science, with a particular focus on fault-tolerant quantum information processing. I aim to understand how environmental factors influence these systems and to develop strategies for leveraging or mitigating the dissipation of quantum information (approaches commonly referred to as dissipation or reservoir engineering). Through our latest preprint, I got interested in the nonlinearities inherent in most couplings between quantum systems. Typically, these nonlinearities are circumvented by operating within specific regimes (e.g., Lamb-Dicke and transmon regimes), often under the assumption of weak interactions and low excitations. However, they are also key components for introducing quantum features, thus necessitating novel effective and intuitive strategies to tackle them. As an initial step in this direction, our work introduces a novel paradigm in reservoir engineering. Using nonlinearities, we reveal a more general theory regarding the dimension, shape, and error-correction properties of quantum state manifolds stabilized through reservoir engineering.

In my daily work, I address few-body problems related to quantum error correction, error characterization, and the implementation of quantum gates in spin and/or bosonic systems. I investigate both continuous (Lindbladian-based) and discrete (gate-based) frameworks to analyze the dynamics and efficiency of these quantum processes.

Links:      Email     Google Scholar     ORCID     GitHub     LinkedIn     @RojkovIvan

news

Aug, 2024
In August, I had the opportunity to visit several research groups across the US. This included Paola Cappellaro and Vladan Vuletić's groups at MIT, Misha Lukin's group at Harvard University (hosted by Johannes Borregaard), Steve Girvin and Shruti Puri's groups at the Yale Quantum Institute (along with Michel Devoret's group), Jeff Thompson's group at Princeton, Victor V. Albert's group at QuICS (University of Maryland), Liang Jiang's group at the University of Chicago (+ Aash Clerk's group), as well as researchers at Caltech from John Preskill's group (Qian Xu) and the AWS Center for Quantum Computing (hosted by Connor Hann). During these visits, I presented our latest work on the stabilization of cat-state manifolds through nonlinear reservoir engineering (read here). I am grateful for the valuable feedback and engaging discussions I had throughout these visits!
Jul, 2024 Our work on stabilized cat-state manifolds using nonlinear reservoir engineering is now available on arXiv. Comments are welcome :)
Jul, 2024 The two-qubit GKP gate paper got accepted in Physical Review Letters!
Mar, 2024 I was invited to give a presentation at the Collège Sismondi (highschool) in Geneva to present the principles of quantum computers and the latest advancements in research.
Jun, 2023 I took part in the Bolder Boulder Quantum Workshop, where I presented a poster, and afterward, I visited JILA and NIST.
Jan, 2023 I visited the research group of Klemens Hammerer at Leibniz Universität Hannover.

selected publications

  1. Bias in Error-Corrected Quantum Sensing
    Ivan Rojkov ,  David Layden ,  Paola Cappellaro ,  Jonathan Home ,  and  Florentin Reiter
    Phys. Rev. Lett. 128, 140503 (2022)
  2. Generation of a Maximally Entangled State Using Collective Optical Pumping
    Maciej Malinowski ,  Chi Zhang ,  Vlad Negnevitsky ,  Ivan Rojkov ,  Florentin Reiter ,  T-L Nguyen ,  Martin Stadler ,  Daniel Kienzler ,  Karan K Mehta ,  and  Jonathan P Home
    Phys. Rev. Lett. 128, 080503 (2022)
  3. Two-Qubit Operations for Finite-Energy Gottesman-Kitaev-Preskill Encodings
    Ivan Rojkov ,  Paul Moser Röggla ,  Martin Wagener ,  Moritz Fontboté-Schmidt ,  Stephan Welte ,  Jonathan Home ,  and  Florentin Reiter
    Phys. Rev. Lett. 133, 100601 (2024)
  4. Characterization of Coherent Errors in Noisy Quantum Devices
    Noah Kaufmann ,  Ivan Rojkov ,  and  Florentin Reiter
    arXiv:quant-ph/2307.08741 (2023)
  5. Stabilization of cat-state manifolds using nonlinear reservoir engineering
    Ivan Rojkov ,  Matteo Simoni ,  Elias Zapusek ,  Florentin Reiter ,  and  Jonathan Home
    arXiv:quant-ph/2407.18087 (2024)