Colorado School of Mines Electrical Engineering

Microwave &
Photonics Lab

We are microwave engineers developing low-noise electromagnetic sensors for remote sensing, Positioning, Navigation and Timing (PNT), Earth observation, communications, and quantum computing. We co-design microwave and photonic integrated circuits to push sensors beyond the limits of conventional analog electronics.

Microwave probe and optical fibers on a photonic integrated chip
Principal Investigator
Gabriel Santamaria-Botello, PhD
Department
Electrical Engineering
Colorado School of Mines
Founded
August 2023
External Funding
$1.7M+ (Lab share)
01

Research thrusts

From kHz to optical · Classical and quantum sensing

1.1RF sensing

Frequency-agile RF sensors.

Chip-scale electro-optic microwave sensors from kHz to tens of GHz.

1.2Quantum networks

Microwave-to-optical quantum transducers.

Photonic integrated circuits for heterogeneous quantum computing networks.

1.3Positioning, Navigation and Timing

Fully photonic mm-wave receivers for time and frequency transfer.

Synchronizing remote optical atomic clocks for Positioning, Navigation and Timing.

1.4Parametric amplification

A new class of STO-based quantum-limited microwave amplifiers.

Strontium titanate as a nonlinear medium to engineer microwave parametric processes, avoiding the magnetic sensitivity issues and frequency limitations of Josephson-junction amplifiers used in most superconducting-qubit platforms today.

1.5EO combs

Packaged broadband electro-optic dual combs for sensing.

General-purpose RF-photonic dual comb generators for LIDAR and gas spectroscopy.

1.6Biomedical

Microwave radiometry for non-invasive thermometry.

Correlation radiometry for 3D spatial focusing and heterodyne architectures for interference cancellation, for non-invasive core body temperature measurement.

Sponsors

$1.7M+External funding secured
(Lab share)

  • DARPA
  • Air Force Office of Scientific Research
  • Colorado Office of Economic Development and International Trade

Partners & Collaborators

  • United States Space Force
  • Bifrost Electronics
  • EPFL
  • University of Colorado Boulder
  • Universidad Carlos III de Madrid
  • University of Otago
  • Tampere University
  • European Space Agency
  • Airbus
02

The PI

Gabriel Santamaria-Botello, PhD

Gabriel Santamaria-Botello

Gabriel Santamaria-Botello is an Assistant Professor in the Electrical Engineering Department at Colorado School of Mines, where his group designs microwave and photonic integrated circuits for RF receivers, transceivers, and sensors. Prior to joining Mines in 2023, he was a Research Associate at the University of Colorado Boulder in the Microwave and RF Research Group. In 2024 he was a Visiting Professor at EPFL's Laboratory of Photonics and Quantum Measurements. He earned his PhD cum laude in 2021 from Universidad Carlos III de Madrid, did a research stay at the University of Otago, and received his B.Sc. in Electrical Engineering from the University of Carabobo. His research spans microwave photonics, quantum sensing, superconducting circuits, remote sensing, radio astronomy and computational electromagnetics.

03

News & highlights

Recent milestones from the lab

Publication · J. Lightwave TechnologyMay 2026 · Journal of Lightwave Technology

Photonic generation and free-space distribution of millimeter waves for portable optical clocks.

In collaboration with CU Boulder and NIST, published in the Journal of Lightwave Technology.
Publication · PreprintarXiv:2510.06176

Integrated photonic mm-wave receiver with sub-ambient noise.

Demonstration of ultra-low-noise millimeter-wave detection in a fully photonic lithium tantalate chip.
Grant · DARPA

Awarded the DARPA MTO SparkTank Pitch Day.

We were awarded the DARPA MTO PitchDay Award, to investigate RF-photonic sensors as part of the technical area "Commercially Catalyzed Defense Deployment". We were recently awarded a third phase to continue our research on photonic-enabled RF sensors.
Bifrost Electronics

Bifrost Electronics raises $4M in venture funding.

Co-Founded by PhD student Connor Denney, Bifrost Electronics is developing a parametric amplifier technology initiated in our lab with the support of an Advanced Industries Grant.
Featured · PublicationJanuary 2025 · Nature 637(8048):1096–1103

Our work on integrated electro-optic frequency combs in lithium tantalate published in Nature.

With collaborators at EPFL, we demonstrated record-span electro-optic frequency comb generation in a fully photonic chip.
04

Selected publications

Recent work since joining Mines

Full list on Google Scholar
05

Talks

Recent international & technical advisory engagements

2026
Antenna Miniaturization Techniques: technical session.
ACES 2026, Applied Computational Electromagnetics Society · Session organizer
ThessalonikiGreece
2025Invited
Fully photonic-integrated low-noise microwave receiver frontends.
ANZCOP 2025, Australian and New Zealand Conference on Optics and Photonics
AucklandNew Zealand
2025
Fundamental limitations of electro-optic electrically small antennas.
PIERS 2025, Progress In Electromagnetics Research Symposium
ChibaJapan
2025
Traveling-wave parametric amplifiers on strontium titanate.
PIERS 2025
ChibaJapan
06

The team

Gabriel Santamaria-Botello
Gabriel Santamaria-Botello
Principal Investigator
Assistant Professor, Electrical Engineering.
Connor Denney
Connor Denney
PhD
Photonic ICs & parametric amplifiers. Founder, Bifrost Electronics.
Steffen Kross
Steffen Kross
PhD
Fully photonic mm-wave receivers.
Cameron Connolly-Hergert
Cameron Connolly-Hergert
Undergraduate researcher (now NIST PREP fellow)
RF metrology.

Alumni

Lisa Elmiladi
Lisa Elmiladi
PhD
Packaged electro-optic dual combs.
Ethan Hansen
Ethan Hansen
MSc · EE
NIST PREP fellow. On-wafer RF and thermoreflectance measurements.
08

Lab capabilities

RF, mm-wave, THz and photonics · test and assembly

Microwave and photonic test benches in one lab: DC–⁠50 GHz electronic measurement, mm-wave and photonics on-wafer probing, THz power metrology and ultra-low-noise lasers, plus in-house wire bonding and fiber-to-PIC packaging.

All equipment
09

Teaching

Electrical & Quantum Engineering at Mines

EENG 430/530
Passive RF and Microwave Devices
Fall 2023, 2024, 2026
EENG 386
Engineering Electromagnetics
Spring 2024, 2026
EENG 532
Low Temperature Microwave Measurements
Fall 2025, 2026
EENG 533
Active RF and Microwave Devices
Spring 2026, 2027
EENG 281
Introduction to Electrical Circuits, Electronics and Power
Spring 2025
10

Our tools

Free, browser-based · built in the lab

tl.mwphotonics.com

Transmission-Line Wave Visualizer

Interactive animation of voltage and current waves on lossless transmission lines: reflections, bounce diagrams, cascaded sections and standing waves.

TeachingEENG 530
sstudio.mwphotonics.com

S-Param Studio

Import Touchstone .sNp files and plot S-parameters on XY or Smith charts, with markers and publication-ready PNG/PDF export.

TouchstoneSmith chart
easyrfpic.mwphotonics.com

easyRFPIC

Layout tool for RF-photonic integrated circuits.

PhotonicsLayout
nc.mwphotonics.com

NC Explorer

NetCDF (.nc) plotter for instrument data. Explore multidimensional sweeps with sliders and 2D, rainbow or 3D plots. Files never leave your computer.

NetCDFData
11

Join the lab

We are looking for a postdoctoral researcher to work on microwave-to-optical quantum transduction for next-generation quantum computing systems. Backgrounds in microwave engineering, superconducting circuits, photonics, or quantum optics are encouraged to apply.

Email to apply