Refereed papers

  1. A. Lingenfelter, M. Yao, A. Pocklington, Y.-X. Wang, A. Irfan, W. Pfaff, A. A. Clerk, Exact Results for a Boundary-Driven Double Spin Chain and Resource-Efficient Remote Entanglement Stabilization. Phys. Rev. X 14, 021028 (2024).
    doi:10.1103/PhysRevX.14.021028, arXiv:2307.09482
  2. Z. Jiang, J. Lim, Y. Li, W. Pfaff, T.-H. Lo, J. Qian, A. Schleife, J.-M. Zuo, V. Novosad, A. Hoffmann, Integrating magnons for quantum information. Applied Physics Letters 123, 130501 (2023).
  3. C. Zhou, P. Lu, M. Praquin, T.-C. Chien, R. Kaufman, X. Cao, M. Xia, R. S. K. Mong, W. Pfaff, D. Pekker, M. Hatridge, Realizing all-to-all couplings among detachable quantum modules using a microwave quantum state router. npj Quantum Inf 9, 54 (2023). doi:10.1038/s41534-023-00723-7, arXiv:2109.06848

Earlier work

Stuff that Wolfgang did in previous lives.

Microsoft Quantum

These result came from efforts to realize a fast and high-fidelity rf readout platform for future topologically protected qubits. They were all in collaboration between Microsoft Quantum researchers and students and postdocs at QuTech at TU Delft.

  1. L. Han, M. Chan, D. de Jong, C. Prosko, G. Badawy, S. Gazibegovic, E. P. A. M. Bakkers, L. P. Kouwenhoven, F. K. Malinowski, and W. Pfaff, Variable and Orbital-Dependent Spin-Orbit Field Orientations in a InSb Double Quantum Dot Characterized via Dispersive Gate Sensing, arXiv:2203.06047.
  2. D. de Jong, C. G. Prosko, L. Han, F. K. Malinowski, Y. Liu, L. P. Kouwenhoven, and W. Pfaff, Controllable Single Cooper Pair Splitting in Hybrid Quantum Dot Systems, arXiv:2208.05154.
  3. D. de Jong, C. G. Prosko, D. M. A. Waardenburg, L. Han, F. K. Malinowski, P. Krogstrup, L. P. Kouwenhoven, J. V. Koski, and W. Pfaff, Rapid Microwave-Only Characterization and Readout of Quantum Dots Using Multiplexed Gigahertz-Frequency Resonators, Phys. Rev. Applied 16, 014007 (2021). arXiv:2103.03659.
    Selected as Editor’s suggestion.
  4. M. Pita-Vidal, A. Bargerbos, C.-K. Yang, D. J. van Woerkom, W. Pfaff, N. Haider, P. Krogstrup, L. P. Kouwenhoven, G. de Lange, and A. Kou, Gate-Tunable Field-Compatible Fluxonium, Phys. Rev. Applied 14, 064038 (2020). arXiv:1910.07978.
    Selected as Editor’s suggestion.
  5. D. de Jong, J. van Veen, L. Binci, A. Singh, P. Krogstrup, L. P. Kouwenhoven, W. Pfaff, and J. D. Watson, Rapid Detection of Coherent Tunneling in an InAs Nanowire Quantum Dot through Dispersive Gate Sensing, Phys. Rev. Appl. 11, 044061 (2019). arXiv:1812.08609.
    Selected as Editor’s suggestion.
  6. J. van Veen, D. de Jong, L. Han, C. Prosko, P. Krogstrup, J. D. Watson, L. P. Kouwenhoven, and W. Pfaff, Revealing charge-tunneling processes between a quantum dot and a superconducting island through gate sensing, Phys. Rev. B 100, (2019). arXiv: 1903.09066.

Schoelkopf Lab at Yale

Results from my time as a postdoc in RSL. These efforts were mainly centered around superconducting cavities and trying to realize microwave quantum networks for modular quantum computing.

  1. C. J. Axline*, L. D. Burkhart*, W. Pfaff*, M. Zhang, K. Chou, P. Campagne-Ibarcq, P. Reinhold, L. Frunzio, S. M. Girvin, L. Jiang, M. H. Devoret, and R. J. Schoelkopf, On-demand quantum state transfer and entanglement be- tween remote microwave cavity memories, Nat. Phys. 14, 705 (2018). arXiv: 1712.05832.
  2. P. Campagne-Ibarcq, E. Zalys-Geller, A. Narla, S. Shankar, P. Reinhold, L. Burkhart, C. Axline, W. Pfaff, L. Frunzio, R. J. Schoelkopf, and M. H. Devoret, Deterministic Remote Entanglement of Superconducting Circuits through Microwave Two-Photon Transitions, Phys. Rev. Lett. 120, 200501 (2018). arXiv: 1712.05854.
  3. T. Brecht, Y. Chu, C. Axline, W. Pfaff, J. Z. Blumoff, K. Chou, L. Krayzman, L. Frunzio, and R. J. Schoelkopf, Micromachined Integrated Quantum Circuit Containing a Superconducting Qubit, Phys. Rev. Appl. 7, 044018 (2017). arXiv: 1611.02166.
  4. W. Pfaff, C. J. Axline, L. D. Burkhart, U. Vool, P. Reinhold, L. Frunzio, L. Jiang, M. H. Devoret, and R. J. Schoelkopf, Controlled release of multiphoton quantum states from a microwave cavity memory, Nat. Phys. 13, 882 (2017). arXiv: 1612.05238.
  5. A. P. Reed, K. H. Mayer, J. D. Teufel, L. D. Burkhart, W. Pfaff, M. Reagor, L. Sletten, X. Ma, R. J. Schoelkopf, E. Knill, and K. W. Lehnert, Faithful conversion of propagating quantum information to mechanical motion, Nat. Phys. 13, 1163 (2017). arXiv: 1703.02548.
  6. C. Axline, M. Reagor, R. Heeres, P. Reinhold, C. Wang, K. Shain, W. Pfaff, Y. Chu, L. Frunzio, and R. J. Schoelkopf, An architecture for integrating planar and 3D cQED devices, Appl. Phys. Lett. 109, 042601 (2016). arXiv: 1604.06514.
  7. T. Brecht, W. Pfaff, C. Wang, Y. Chu, L. Frunzio, M. H. Devoret, and R. J. Schoelkopf, Multilayer microwave integrated quantum circuits for scalable quantum computing, npj Quantum Inf 2, 16002 (2016). arXiv: 1509.01119.
  8. A. Narla, S. Shankar, M. Hatridge, Z. Leghtas, K. M. Sliwa, E. Zalys-Geller, S. O. Mundhada, W. Pfaff, L. Frunzio, R. J. Schoelkopf, and M. H. Devoret, Robust Concurrent Remote Entanglement Between Two Superconducting Qubits, Phys. Rev. X 6, 031036 (2016). arXiv: 1603.03742.
  9. M. Reagor, W. Pfaff, C. Axline, R. W. Heeres, N. Ofek, K. Sliwa, E. Holland, C. Wang, J. Blumoff, K. Chou, M. J. Hatridge, L. Frunzio, M. H. Devoret, L. Jiang, and R. J. Schoelkopf, Quantum memory with millisecond coherence in circuit QED, Phys. Rev. B 94, 014506 (2016). arXiv: 1508.05882.
  10. T. Brecht, M. Reagor, Y. Chu, W. Pfaff, C. Wang, L. Frunzio, M. H. Devoret, and R. J. Schoelkopf, Demonstration of superconducting micromachined cavities, Appl. Phys. Lett. 107, 192603 (2015). arXiv: 1509.01119.

Hanson Lab at TU Delft (Netherlands)

Results from my PhD work in the group of Ronald Hanson. The bulk of this was to realize quantum networks using single dopant spins in diamond.

  1. W. Pfaff, B. J. Hensen, H. Bernien, S. B. van Dam, M. S. Blok, T. H. Taminiau, M. J. Tiggelman, R. N. Schouten, M. Markham, D. J. Twitchen, and R. Hanson, Unconditional quantum teleportation between distant solid-state quantum bits, Science 345, 532 (2014). arXiv: 1404.4369.
    Highlighted in a Science perspective: J. Morton and M. Atature, A gem of a quantum teleporter. Science 345, 510 (2014).
    Work featured in international news media: New York Times, The Telegraph, BBC, …
  2. H. Bernien, B. Hensen, W. Pfaff, G. Koolstra, M. S. Blok, L. Robledo, T. H. Taminiau, M. Markham, D. J. Twitchen, L. Childress, and R. Hanson, Heralded entanglement between solid-state qubits separated by three metres, Nature 497, 86 (2013). arXiv: 1212.6136.
    Highlighted in Nature News.
  3. W. Pfaff, T. H. Taminiau, L. Robledo, H. Bernien, M. Markham, D. J. Twitchen, and R. Hanson, Demonstration of entanglement-by-measurement of solid-state qubits, Nat. Phys. 9, 29 (2013). arXiv: 1206.2031.
  4. W. Pfaff, A. Vos, and R. Hanson, Top-down fabrication of plasmonic nanostructures for deterministic coupling to single quantum emitters, J. Appl. Phys. 113, 024310 (2013). arXiv: 1301.1939.
  5. T. van der Sar, J. Hagemeier, W. Pfaff, E. Heeres, S. Thon, H. Kim, P. Petroff, O. Tjerk, D. Bouwmeester, and R. Hanson, Effect of a nanoparticle on the optical properties of a photonic crystal cavity: Theory and experiment, J. Opt. Soc. Am. B 29, 698 (2012).
  6. T. van der Sar, J. Hagemeier, W. Pfaff, E. C. Heeres, S. M. Thon, H. Kim, P. M. Petroff, T. H. Oosterkamp, D. Bouwmeester, and R. Hanson, Deterministic nanoassembly of a coupled quantum emitter–photonic crystal cavity system, Appl. Phys. Lett. 98, 193103 (2011). arXiv: 1008.4097.

Undergrad, University of Regensburg (Germany)

Some stuff I helped with as a fledgling scientist, in the group of Christoph Strunk.

  1. O. Vavra, W. Pfaff, R. Monaco, M. Aprili, and C. Strunk, Current-controllable planar S-(S/F)-S Josephson junction, Appl. Phys. Lett. 102, 072602 (2013).
  2. O. Vavra, W. Pfaff, and C. Strunk, Planar S-(S/F)-S Josephson junctions induced by the inverse proximity effect, Appl. Phys. Lett. 95, 062501 (2009).