Senior RF Engineer: Quantum Sensing & Test Systems

Infleqtion; Louisville (CO); On-site; USD 145,000 - 170,000; Full time

Benefits offered by this job

100% company-paid medical, dental, and

Employer-funded Health Savings Account

Unlimited PTO

401(k) match

Equity Program

Company-paid Life and AD&D Insurance

Flexible Savings Account

Paid FMLA, Maternity/Paternity Leave

Employee Assistance Program

Student Loan Repayment

Job summary

Infleqtion in the United States is seeking a hands-on RF Engineer to establish and own the RF and electromagnetics discipline within the QRF team. You will lead design, modeling, integration, calibration, and verification of broadband RF hardware and test environments for sensor heads and integrated systems.

The role emphasizes field delivery, impedance budgets, and traceable measurements. You will work on simulations, automation in Python, and collaboration with physicists and

Qualifications

• Bachelor’s degree in electrical engineering, applied physics, electromagnetics, or a closely related field, or equivalent practical experience.
• At least five years of relevant RF, microwave, electromagnetics, or related hardware development experience.
• Hands-on lab experience with VNA, spectrum analyzers, signal generators, oscilloscopes, power meters, and RF probes.
• Experience with impedance matching, gain/loss, noise, phase noise, and measurement uncertainty.
• Experience with RF, circuit, or electromagnetic simulation tools (HFSS, CST, ADS, AWR, COMSOL, FEKO, etc.).
• Experience using Python, MATLAB, LabVIEW for automation, testing, data analysis.
• Ability to work independently, document work, and learn atomic physics concepts as needed.

Responsibilities

• Own RF and electromagnetic requirements, architectures, interfaces, budgets, and verification methods.
• Design, simulate, build, and characterize RF structures (electrodes, resonators, antennas, fixtures).
• Develop RF signal generation, amplification, filtering, frequency conversion, and LO approaches.
• Build and improve RF test environments, including field generation and calibration configurations.
• Define measurements for field strength, frequency response, impedance, S-parameters, phase, shielding, noise, dynamic range.
• Lead RF hardware bring-up, troubleshooting, root-cause analysis across configurations.
• Use electromagnetic/circuit simulation to guide design and reconcile models with data.
• Develop Python or comparable automation for instrument control, data analysis, reporting.
• Collaborate with physicists to relate RF behavior to atomic response.
• Document designs, interfaces, calibration methods, test procedures, results, risk, and recommendations.

Skills

Impedance matching

Gain & loss

Noise

Dynamic range

Phase noise

Spurious response

Measurement uncertainty

RF design

Python

MATLAB

LabVIEW

Education

Bachelor’s degree in electrical engineering, applied physics, electromagnetics, or closely related field

Tools

Vector network analyzers

Spectrum analyzers

Oscilloscopes

Signal generators

Power meters

RF probes

Job description

Infleqtion in the United States is seeking a hands-on RF Engineer to establish and own the RF and electromagnetics discipline within the QRF team. You will lead design, modeling, integration, calibration, and verification of broadband RF hardware and test environments for sensor heads and integrated systems.

The role emphasizes field delivery, impedance budgets, and traceable measurements. You will work on simulations, automation in Python, and collaboration with physicists and