Clocks that agree without a conductor

I do not just ask what if. I ask how do we get it done.

My sweet spot is the bridge between basic science and real-world application. My field is nonlinear dynamics — specifically what happens when many oscillators are coupled and the signals between them arrive late. For years that was a blackboard problem. Then we patented it, then we built it at 24 gigahertz across half a kilometre, and now I lead the development of hybrid analog-digital computers at anabrid.

I am grateful to all the people I have worked with and learned from: Frank Jülicher, Ulrich Behn, Gerhard Fettweis, Frank Ellinger, Wolfgang Rave, David Jörg, Alexandros Pollakis, Dimitrios Prousalis, Christian Hoyer, Jens Wagner, Rabia Riaz, Johannes Fritzsche, Nirmal Punetha, Shamik Gupta, Luis Morelli, Andrew Oates, Saúl Ares, Dirk Killat, Deborah Schmidt, Bernd Ulmann, Shrish Roy, Daniel Thürck, Michael Steck, Sara Obergassel and Kerstin Hafemeister, along with many colleagues, students and guest scientists not named here. Very little of this was done alone.

As Chief Scientific Officer I am responsible for our scientific direction, for hardware development, and for the technical conversation with customers. The REDAC, the largest reconfigurable discrete analog computer in operation, was designed, built and commissioned by the team I lead. It now carries three research projects in the DLR Quantum Computing Initiative.

Before industry I spent fifteen years at the Max Planck Institute for the Physics of Complex Systems. I directed the VIP+ validation project on phase-locked loop synchronization together with Fraunhofer IZM and TU Dresden. It proved that high-level theory survives the rigours of a real application. I also learned there that the strongest results do not come out of silos. They come from interdisciplinary teams, a real market need, and a clear view of where you are going.

On leadership, from the lab to the gridiron. I played American football with the Dresden Monarchs, and it taught me that a perfect playbook is worth nothing without execution, discipline, and a team that trusts each other under pressure. I run research and development the same way. My job is to keep a culture where any question can be asked and where new ideas still have to meet a performance bar.

Happy to talk about analog and unconventional computing, synchronization, energy-efficient computation, and how research moves out of the institute and into a product. Get in touch.

In complex systems the synchronization and coordination of many individual parts plays a crucial role. Examples range from multi-core computer architectures, power grid networks, coupled laser arrays, and wireless communication all the way to large groups of interacting cells during embryogenesis or in the brain. Information transmission necessary for the coordination of such large groups of interacting parts is often not instantaneous. This can introduce communication delays within the system which cannot be neglected. In associated mathematical models such delays in the interaction terms lead to qualitatively new behavior. Phenomena like coexisting stable solutions and dynamic behavior that depends nonlinearly on different system parameters can be observed.

Detailed analysis of such systems is required to built efficiently designed industrial parts such as power saving micro-electronics or precisely synchronized clocks, as well as to understand the evolution and function of biological systems. Interdisciplinary teamwork, enthusiasm and strong communication skills to bridge different approaches and fields are important to successfully tackle these complex problems.

Journal articles

• C. Hoyer, L. Wetzel, D. A. Prousalis, J. Wagner, F. Jülicher, F. Ellinger, “Entrainment of mutually synchronized spatially distributed 24 GHz oscillators”, IEEE Transactions on Circuits and Systems I 70(7), 2665–2678 (2023)
• N. Punetha, L. Wetzel, “How clock heterogeneity affects synchronization and can enhance stability”, Physical Review E 106, 054216 (2022)
• L. Wetzel, D. A. Prousalis, R. F. Riaz, C. Hoyer, N. Joram, J. Fritzsche, F. Ellinger, F. Jülicher, “Network synchronization revisited: time delays in mutually coupled oscillators”, IEEE Access 10, 80027–80045 (2022)
• C. Hoyer, L. Wetzel, D. A. Prousalis, J. Wagner, F. Jülicher, F. Ellinger, “Mutual synchronization of spatially distributed 24 GHz oscillators up to distances of 500 m”, IEEE Transactions on Circuits and Systems II 69(9), 3689–3693 (2022)
• D. A. Prousalis, L. Wetzel, “Synchronization in the presence of time delays and inertia: stability criteria”, Physical Review E 105, 014210 (2022)
• D. Métivier, L. Wetzel, S. Gupta, “Onset of synchronization in networks of second-order Kuramoto oscillators with delayed coupling: exact results and application to phase-locked loops”, Physical Review Research 2, 023183 (2020)
• L. Wetzel, D. J. Jörg, A. Pollakis, W. Rave, G. Fettweis, F. Jülicher, “Self-organized synchronization of digital phase-locked loops with delayed coupling in theory and experiment”, PLOS ONE 12(2), e0171590 (2017)
• A. Pollakis, L. Wetzel, D. J. Jörg, W. Rave, G. Fettweis, F. Jülicher, “Synchronization in networks of mutually delay-coupled phase-locked loops”, New Journal of Physics 16, 113009 (2014)

Conference papers

• C. Hoyer, L. Wetzel, D. A. Prousalis, J. Wagner, F. Jülicher, F. Ellinger, “Stability analysis of mutually synchronized spatially distributed 24 GHz oscillators”, IEEE International Instrumentation and Measurement Technology Conference (I2MTC), 2022
• C. Hoyer, D. A. Prousalis, L. Wetzel, R. F. Riaz, J. Wagner, F. Jülicher, F. Ellinger, “Mutual synchronization with 24 GHz oscillators”, IEEE International Symposium on Circuits and Systems (ISCAS), Daegu, 1–5 (2021)
• R. F. Riaz, D. A. Prousalis, C. Hoyer, J. Wagner, F. Ellinger, F. Jülicher, L. Wetzel, “Stability and transient dynamics of PLLs in theory and experiments”, European Conference on Circuit Theory and Design (ECCTD), Sofia, 1–4 (2020)
• D. J. Jörg, A. Pollakis, L. Wetzel, M. Dropp, W. Rave, F. Jülicher, G. Fettweis, “Synchronization of mutually coupled digital PLLs in massive MIMO systems”, IEEE International Conference on Communications (ICC), 1716–1721 (2015)
• L. Wetzel, A. Pollakis, D. J. Jörg, W. Rave, G. Fettweis, F. Jülicher, “Self-organized synchronisation in massive MIMO inspired by biological systems”, IEEE Workshop on Molecular, Biological and Multi-Scale Communications (MBMC), 2015

Theses and preprints

• L. Wetzel, “Effect of distributed delays in systems of coupled phase oscillators”, PhD thesis, TU Dresden and MPI-PKS (2012) [qucosa]
• L. Wetzel, L. G. Morelli, A. C. Oates, F. Jülicher, S. Ares, “Synchronization of phase oscillators in the presence of distributed delays”, arXiv:1206.2288 (2012)
• L. Wetzel, “Stability and statistical properties of stochastic delay differential equations”, diploma thesis, University of Leipzig (2008)

Further work on hybrid analog-digital computing is in preparation or under review.

Selected talks

• Analog Computing Days 2026, Frankfurt — workshop and talk
• WCCM 2026, World Congress in Computational Mechanics, Munich — conference contribution
• AFQC 2026, DLR Quantum Computing Initiative, Düsseldorf
• Summer School, TU Dresden, 04/2026 — lecture course
• HPCN Workshop, DLR Dresden, 2026
• Falling Walls Science Summit, Berlin, 2025 — speaker
• REDAC handover to the DLR, 2025, and the accompanying REDAC lecture series
• DPG-Kolleg, Ulm, 05/2025
• Digital Twin, DLR Dresden, 2025, and the DLR Institute of Aerodynamics and Flow Technology, 07/2025
• Chair for Network Dynamics, TU Dresden, 2025
• German Quantum Computing Initiative, All Hands Meeting, Hamburg, 11/2024 “From ancient Greece to the moon and back for quantum computing”
• International Workshop on Ising Machines, Messina, 04/2024 “The role of inert oscillator response and signaling time delays when scaling up Ising machines based on electronic oscillators”
• ENOC 2024, European Nonlinear Dynamics Conference, 02/2024 — coupled phase-locked loops
• DLR Oberpfaffenhofen, 2024, and DLR-QCI Showcase Day, Ulm, 11/2023
• QUANTUM 2023 and the Mikrosystemtechnik-Kongress, Dresden, 2023
• Workshop: Intelligent Machines? Self-Organized Nonlinear Dynamics of Machines across Scales, Dresden, 06/2022 “Ising machines — analog computing using coupled oscillators”
• Joint conference of the European Frequency and Time Forum and the IEEE International Frequency Control Symposium, Paris, 04/2022 “Mutual network synchronization: how precise phase relations can be achieved in the presence of large cross-coupling time delays”
• Presentation at Naventik GmbH, Chemnitz, 04/2021 “Entrainment and self-organized synchronization — spatially distributed clocks and their applications”
• IQ Preis Mitteldeutschland, 05/2021, virtual pitch “Navigation mit geschlossenen Augen — Richtungshören innerhalb existierender Mobilfunkarchitektur”
• Colloquium, Center for Advancing Electronics Dresden (cfaed), 09/2019 “Self-organized synchronization — from localized time references to spatially extended clocking”
• Dynamics Days, Corfu, 06/2016 “Phase dynamics of delay-coupled electronic clocks with filter induced memory effects”
• Graduate Lecture, Faculty of Science, Department of Mathematics, TU Dresden, 01/2015 “Synchronization: embryonic development to electronic networks”
• Dynamics Days, Baltimore, 01/2012 “Effect of distributed delays on synchronization dynamics”
• Meeting of the German Physical Society, Dresden (DPG 03/2011) “Effect of distributed delays on synchronization dynamics”
• Meeting of the German Physical Society, Regensburg (DPG 03/2010), and the PhD Circle Meeting, Amsterdam, 04/2010 “Distributed vs fixed delay in a system of coupled phase oscillators”

Posters

• 675. WE-Heraeus Seminar: Delayed Complex Systems, 2018 “Design centering quantifies basin stability of synchronized states in mutually delay-coupled electronic clocks”
• Workshop on Dynamics of Coupled Oscillators: 40 Years of the Kuramoto Model, MPI-PKS, 07/2015 “Robust synchronization in electronic networks with delay coupled distributed clocks”
• Physics of Living Matter, London, 09/2012 “Reconstructing the segmentation clock oscillator” (third author)
• Meeting of the German Physical Society, Berlin (DPG 03/2012) “Effects of distributed delay in the coupling of phase oscillators for m-twist solutions”
• Delayed Complex Systems, MPI-PKS, 10/2009 “Coupled phase oscillators with distributed delay”
• Annual Zebrafish Meeting, Rome, 07/2009 “The effects of intercellular communication in biological clocks”
• Meeting of the German Physical Society, Dresden (DPG 03/2009) “Distributed time delay in the Kuramoto model of coupled oscillators”

• “Self-synchronizable network”
  Frank Jülicher, Lucas Wetzel, David J. Jörg, Gerhard Fettweis, Wolfgang Rave, Alexandros Pollakis
  European Patent EP 2 957 982 A1
  WIPO (PCT) WO2015193512A1
  United States US20170139438A1
  South Korea KR102029320B1
  China CN106462177B
  Taiwan TWI721948B

Further applications on analog and hybrid computing are in prosecution at anabrid GmbH.

Professional experience

07/2024 – today

Chief Scientific Officer, anabrid GmbH
Direct the scientific strategy of a deep-tech company building hybrid analog-digital computers, reporting to and advising the CEO. Led the design, construction and commissioning of the REDAC, the largest reconfigurable discrete analog computer in operation — now the computational backbone of three research projects inside the DLR Quantum Computing Initiative. Responsible for hardware development and for the technical side of customer acquisition, with scope extending into software and integrated-circuit development. Driving the move from discrete components towards integrated hardware, and accountable for the scientific output of the company: papers, deliverables to public funding bodies, and patent-relevant intellectual property.

01/2023 – 06/2024

Project Leader and Senior Scientist, anabrid GmbH
Built the research and development line on modern hybrid computer architectures, from architecture concept through to a working prototype. Established the scientific method and the benchmarking practice the company now uses to qualify analog computing results: every case study pairs the analog run against a digital reference solver and reports accuracy and energy, so a result is reproducible rather than anecdotal.

07/2019 – 12/2022

Principal Investigator, BMBF VIP+ validation project “PLL synchronization”, Max Planck Institute for the Physics of Complex Systems (MPI-PKS), Dresden
Applied for and won 1.5 million Euro from the German Federal Ministry of Education and Research to carry results from basic research towards industrial application. Ran the consortium with the Chair for Circuit Design and Network Theory at TU Dresden and Fraunhofer IZM ASSID. Demonstrated stable mutual synchronization of spatially distributed 24 GHz oscillators over distances up to 500 m, locking completely in phase despite cross-coupling delays far longer than a single oscillation period; the model analysis then informed the architecture design at 60 GHz. Carried out the market analysis, identified the unique selling points, and led the communication with industry partners. More than fifteen publications came out of the project.

11/2017 – 12/2022

Group and Project Leader, MPI-PKS, Dresden
Coordinated research with an international team of twelve scientists across physics, electrical engineering and systems design. Supervised a doctoral student and visiting scientists on separate research projects, and presented the work at international conferences.

04/2015 – 03/2017

Project Leader, MPI-PKS, Dresden
Coordinated an international team of ten scientists. Initiated the outreach to industry and to Fraunhofer institutes that later carried the validation project. Founded and ran the institute's biweekly Nuclear Lounge science event.

11/2012 – 02/2015

Postdoctoral Researcher, MPI-PKS, Dresden
Co-invented and patented a synchronization concept for distributed electronic systems. Opened the collaboration with the Vodafone Chair for Mobile Communications Systems at TU Dresden, within the Cluster of Excellence Center for Advancing Electronics Dresden (cfaed).

2015, 2017

Parental leave — three months in 2015 and nine months in 2017, the second period combined with part-time patent and project management.

Education

2008 – 2012

Dr. rer. nat. in Physics, TU Dresden
Carried out at MPI-PKS under Prof. Frank Jülicher. Thesis: Effect of distributed delays in systems of coupled phase oscillators.

2006 – 2008

Diploma in Physics, University of Leipzig
Supervisor: Prof. Ulrich Behn. Thesis: Stability and statistical properties of stochastic delay differential equations. Examinations in experimental physics (1.0), theoretical physics (1.3), stochastic processes and nonlinear dynamics (1.3).

2002 – 2006

Studies of Physics, University of Leipzig and ETH Zürich
Examinations in micro- and nanosystems (1.3), management and organization (2.0).

1998 – 1999

High school year, United States
Grade point average 1.0, Principal's List, state mathematics award.

Funding, intellectual property and recognition

2019

BMBF VIP+ validation grant, 1.5 million Euro, as applicant and principal investigator. Partners: TU Dresden and Fraunhofer IZM ASSID.

granted

European Patent EP 2 957 982, “Self-synchronizable network”, also granted in the United States, China, Taiwan and Korea — see Patents.

ongoing

Member of the German Physical Society (DPG). Reviewer for IEEE conferences and journals.

• Physics and mathematics
  • Nonlinear dynamics, delay differential equations, stochastic differential equations
  • Coupled-oscillator networks and synchronization theory; Kuramoto models of first and second order
  • Linear stability analysis, basin stability, bifurcation and parameter-space analysis
  • Control theory: transfer functions, gain and phase margins, stability criteria under delay
• Computing and hardware
  • Analog and hybrid analog-digital computing: architecture, programming, operation
  • Phase-locked loops from the phase model down to the circuit level
  • Oscillator-based computing and Ising machines; central pattern generators
  • Numerical solution of PDEs — wave, Burgers, Navier–Stokes, diffusion with variable coefficients
  • Neural networks on analog substrates: mapping trained models, neural ODEs, reservoir computing
  • Gate-based quantum circuits and their classical simulation
  • Error and accuracy analysis of analog computation, energy accounting, benchmark methodology
• Tools
  • Python (scientific stack, simulation libraries), C++, MATLAB & Simulink, Mathematica
  • LTspice and circuit-level simulation, VHDL
  • Qiskit and QASM
  • LaTeX, Linux, Git, Qt, Gnuplot, Inkscape & Gimp
• Leading the work
  • Scientific strategy and R&D portfolio direction across many parallel projects
  • Research funding: proposals and sketches to BMFTR/BMBF, DLR, ZIM and EU-adjacent instruments
  • Contract research: work packages, deliverables, acceptance and reporting
  • Intellectual property: invention disclosures, prior-art and patentability searches, prosecution support
  • Supervision of doctoral students, theses and visiting scientists; hiring and onboarding
  • Representing the science to funding bodies, industry partners and the public
  • Project management certification
• Languages
  • German: mother tongue
  • English: full professional proficiency, Cert. “UNIcert III”
  • French and Spanish: elementary proficiency

2025 – today

Running backs coach, Dresden Monarchs, German Football League (GFL). Licensed since 2026.

2014 – today

Mentoring of doctoral students at TU Dresden and of visiting scientists at MPI-PKS, and supervision of bachelor and master theses at anabrid. Several mentees have gone on to lead their own projects.

2010 – today

Science communication at the Long Night of the Sciences and in schools.

01/2015 – 05/2015

Art & Science, Flock of Happenings (Florian Dombois), Dresden

06/2013 – 04/2015

Organizer, Nuclear Lounge after-science event, MPI-PKS

12/2010 – 12/2014

Reader, Christmas Stories, Barockviertel Dresden

05/2011 – 04/2012

Mentoring of high school students, project “Die Komplizen”

10/2010 – 03/2011

Teaching assistant for the practical training in experimental physics, TU Dresden

09/2009 – 10/2009

Assistant trainer, American Football, Team Saxony

10/2008 – 03/2009

Teaching assistant for mathematical methods in physics, TU Dresden

09/2007 – 10/2007

Student assistant for an introductory course on physics & mathematics, University of Leipzig

12/2004 – 03/2007

Private tutoring of students in physics

06/2003 – 07/2003

Practical training at the Leibniz Institute of Surface Modification, epitaxial growth of GaAs semiconductors

09/2001 – 06/2002

Community service, University Hospital Leipzig, oncology ward

08/2001 – 09/2001

Practical training at Sächsische Bau- & Restaurierungswerkstätten, management

• Machine learning and artificial intelligence, electronic prototyping, science fiction literature, politics, piano, judo, skiing and snowboarding, hiking
• American football at semi-professional level from 2004 to 2015 — Leipzig Lions, Zurich Renegades, Dresden Monarchs. Team captain and vice-champion of the German Football League in 2013. Now coaches the team's running backs.