Leonardo Andreta de Castro

Physicist and software developer

Professional experience

2023–current Staff Software Engineer, Quantum Product Q-CTRL Pty. Ltd. (Sydney, NSW, Australia).
2021–2023 Lead Software Engineer, Quantum Control (Australia) Q-CTRL Pty. Ltd. (Sydney, NSW, Australia).
2019–2021 Senior Quantum Control Engineer Q-CTRL Pty. Ltd. (Sydney, NSW, Australia).
2018–2019 Postdoctoral Associate Duke University (Durham, NC, United States).

Education

2012–2016 Doctorate in Physics University of São Paulo (São Carlos, SP, Brazil).
Thesis: “Protection of quantum systems and the measurement postulate”. Supervisor: Reginaldo de Jesus Napolitano.
  • Published papers exploring the relationship between quantum measurement and protection of quantum states.
  • Published articles on historical and didactic aspects of quantum mechanics.
  • Tutored undergraduate physics students on Electromagnetism.
2010–2012 Master's Degree in Physics University of São Paulo (São Carlos, SP, Brazil).
Thesis: “Quantum error correction during logical gates and finite-time syndrome measurements”. Supervisor: Reginaldo de Jesus Napolitano.
Grant: “Quantum error-correction theory during logical operations and finite-duration syndrome measurements”. Agency: The São Paulo Research Foundation — FAPESP.
  • Researched the intersection between quantum error correction and measurement theory.
  • Wrote software in C to simulate the effects of frequent quantum measurements.
2006–2009 Bachelor's Degree in Physics University of São Paulo (São Carlos, SP, Brazil).
Grant: “Decoherence in a two-qubit system and error correction theory”. Agency: The São Paulo Research Foundation — FAPESP.
  • Developed numerical software in FORTRAN for simulation of physical systems as part of coursework.
  • Researched continuous dynamical decoupling as part of an undergraduate research grant award.

Selected papers

[Harrison Ball, Michael J. Biercuk, André R. R. Carvalho, Jiayin Chen, Michael Hush, Leonardo Andreta de Castro, Li Li, Per J. Lieberman, Harry J. Slatyer, Claire Edmunds, Virginia Frey, Cornelius Hempel, Alistair Milne]. “Software tools for quantum control: Improving quantum computer performance through noise and error suppression” . Quantum Science and Technology 6, 044011 (2021). DOI: 10.1088/2058-9565/abdca6, arXiv: 2001.0406.
[Swarnadeep Majumder, Leonardo Andreta de Castro, Kenneth R. Brown]. “Real-time calibration with spectator qubits” . npj Quantum Information 6, 19 (2020). DOI: 10.1038/s41534-020-0251-y, arXiv: 1907.03864.
[Michael G. Newman, Leonardo Andreta de Castro, Kenneth R. Brown]. “Generating fault-tolerant cluster states from crystal structures” . Quantum 4, 295 (2020). DOI: 10.22331/q-2020-07-13-295, arXiv: 1909.11817.
[Carlos Alexandre Brasil, Leonardo Andreta de Castro]. “Understanding the pointer states” . European Journal of Physics 36, 065024 (2015). DOI: 10.1088/0143-0807/36/6/065024, arXiv: 1508.04101.
[Carlos Alexandre Brasil, Leonardo Andreta de Castro, Reginaldo de Jesus Napolitano]. “Protecting a quantum state from environmental noise by an incompatible finite-time measurement” . Physical Review A 84, 022112 (2011). DOI: 10.1103/PhysRevA.84.022112, arXiv: 1106.4537.
[Leonardo Andreta de Castro, Olímpio Pereira de Sá Neto, Carlos Alexandre Brasil]. “An introduction to quantum measurements with a historical motivation” . Acta Physica Slovaca 69, 1 (2019). arXiv: 1908.03949.
[Leonardo Andreta de Castro, Carlos Alexandre Brasil, Reginaldo de Jesus Napolitano]. “Weak values in collision theory” . Annals of Physics 392, 272-286 (2018). DOI: 10.1016/j.aop.2018.03.014, arXiv: 1803.07110.
[Leonardo Andreta de Castro, Carlos Alexandre Brasil, Reginaldo de Jesus Napolitano]. “Elliptical orbits in the phase-space quantization” . Revista Brasileira de Ensino de Física 38, e3318 (2016). DOI: 10.1590/1806-9126-RBEF-2016-0067, arXiv: 1605.08027.
[Leonardo Andreta de Castro, Reginaldo de Jesus Napolitano]. “Error correction in short time steps during the application of quantum gates” . Annals of Physics 367, 199-211 (2016). DOI: 10.1016/j.aop.2016.01.014, arXiv: 1109.4796.
[Carlos Alexandre Brasil, Leonardo Andreta de Castro, Reginaldo de Jesus Napolitano]. “Efficient finite-time measurements under thermal regimes” . European Physical Journal Plus 129, 206 (2014). DOI: 10.1140/epjp/i2014-14206-0, arXiv: 1309.3621.
[Carlos Alexandre Brasil, Leonardo Andreta de Castro, Reginaldo de Jesus Napolitano]. “How much time does a measurement take?” . Foundations of Physics 43, 642-655 (2013). DOI: 10.1007/s10701-013-9707-7, arXiv: 1109.4613.
More papers

Conference talks

[Leonardo Andreta de Castro, Pak Hong Leung, Pavithran Sridharan Iyer, Kenneth R. Brown]. "Characterizing unwanted motional coupling in Mølmer–Sørensen gates". APS March Meeting 2019 (Boston, MA, United States).

In this conference we presented a talk where we discussed how to derive the equation that describe errors for certain types of two-qubit gates in ion trap quantum computers.

Conference posters