RF / Electromagnetics Engineer

Infleqtion•Louisville, CO

2d•Onsite

About The Position

Infleqtion is a global quantum technology company solving the world’s most challenging problems. The company harnesses quantum mechanics to build and integrate quantum computers, sensors, and networks. From fundamental physics to leading edge commercial products, Infleqtion enables “quantum everywhere” through our ecosystem of devices and platforms. This role focuses on RF architecture design, electromagnetic structures, and EM measurement/calibration in support of advanced quantum and atomic sensor systems. The engineer will serve as a senior technical contributor responsible for developing RF test environments, designing and characterizing EM structures, contributing to LO and signal-chain architecture, and translating experimental results into clear technical direction and measurable system performance. Much of the test and characterization work is in the RF and microwave regime, while familiarity with lower-frequency design and components is also valuable. This is a fully onsite role based in Boulder or Louisville, Colorado. The position emphasizes technical ownership, cross-functional coordination, and clear communication of progress and risk to leadership. Prior experience with atomic or quantum sensors is helpful but not required.

Requirements

BS or MS in Electrical Engineering, Physics, Applied Physics, Electromagnetics, or a related field
5-10+ years of experience in RF, microwave, electromagnetics, antenna, or advanced sensor hardware/system development
Demonstrated experience designing and characterizing electrodes, RF/EM structures, test hardware, or related components
Experience with free-space or radiated RF measurements, calibration methods, and controlled test environment development
Experience contributing to RF architecture or signal-chain design across low-frequency through microwave operation
Strong hands-on RF lab skills with instrumentation such as vector network analyzers, spectrum analyzers, signal generators, oscilloscopes, and power meters
Ability to take ownership of technical tasks, coordinate with internal teams and subcontractors, and communicate progress and risks effectively
Experience using EM simulation and scripting tools to support design, test, automation, and troubleshooting
U.S. citizenship preferred due to the nature of customers, programs, and potential export-controlled work
This position may require access to information protected under U.S. export control laws and regulations, including the Export Administration Regulations (EAR) and the International Traffic in Arms Regulations (ITAR). Please note that any offer for employment may be conditioned on authorization to receive software or technology controlled under these U.S. export control laws and regulations without sponsorship for an export license.

Nice To Haves

Strong Python skills for lab automation, data processing, and technical reporting
Experience with HFSS and/or other EM simulation tools for RF and electromagnetic design
Experience specifying, designing, or building anechoic chambers, radiated test setups, or other controlled RF test environments
Experience with directionality characterization, field mapping, or free-space calibration techniques
Experience with low-phase-noise LO chains, synthesizers, mixers, or frequency-conversion architectures
Experience with atomic or quantum sensors, government-funded R&D programs, or other advanced sensing applications

Responsibilities

Own simulation, design, build, and characterization of electrodes and other RF/EM structures supporting sensor and test system development
Develop free-space RF testbeds and controlled RF environments, including requirements definition, design support, build-out, validation, and continuous improvement
Define and execute EM measurement and calibration methods for radiated field strength, coupling, shielding, and measurement uncertainty
Develop calibration and measurement approaches for controlled-source and signal-of-opportunity field characterization
Contribute to RF architecture development across low-frequency through microwave operation, including signal-chain partitioning and interface definition
Contribute to local oscillator architecture, generation, and distribution approaches for lower- and higher-frequency operation
Evaluate LO leakage, spurious responses, phase noise, and coupling paths, and recommend mitigations
Build and maintain LO noise, signal-chain, and system-level link budgets to support design trades and performance analysis
Support development of frequency conversion and analog interface approaches, including baseband-to-IF concepts as needed
Lead EM simulations to guide hardware design, measurement setup design, and interpretation of test results
Define RF performance metrics and comparison frameworks that support clear datasheet-style communication for novel sensing capabilities
Assist in the design and execution of directionality characterization experiments and related validation plans
Specify requirements for internal or external RF test environments and coordinate with vendors or subcontractors as needed
Collaborate with physicists, electrical engineers, mechanical engineers, software engineers, and external partners to integrate technical contributions
Develop automation, instrument control, data processing, and reporting workflows for RF/EM test activities
Execute hardware bring-up, calibration, troubleshooting, and root-cause analysis across prototype and integrated systems
Document designs, test methods, calibration procedures, and results to support technical reviews and future development
Communicate technical progress, trade studies, risks, and recommendations clearly to leadership and cross-functional teams
Support lab and field testing, proposal activities, customer demonstrations, and other program needs as required