Senior Photonics Engineer, Free-Space Optics

K2 is building the largest and highest-power satellites ever flown, unlocking performance levels previously out of reach across every orbit. Backed by over $1 billion in total funding from leading investors including Altimeter Capital, ICONIQ, Kleiner Perkins, Lightspeed Venture Partners, Redpoint Ventures, and T. Rowe Price — and with over $1 billion in signed contracts across commercial and US government customers, we're mass-producing the highest-power satellite platforms ever built for missions from LEO to deep space.

The rise of heavy-lift launch vehicles is shifting the industry from an era of mass constraint to one of mass abundance, and we believe this new era demands a fundamentally different class of spacecraft. Engineered to survive the harshest radiation environments and to fully capitalize on today's and tomorrow's massive rockets, K2 satellites deliver unmatched capability at constellation scale and across multiple orbits.

With multiple launches in 2027 and plans to scale to 100 satellites a year, we're Building Bigger — helping develop the solar system and build toward a Kardashev Type II (K2) civilization. If you are a motivated individual who thrives in a fast-paced environment and you're excited about contributing to the success of a high-growth Series D-funded company, we'd love for you to apply.

The Role

K2's ambitions extend beyond the satellite bus. By designing and operating our own spacecraft and regularly manifesting hardware to orbit, K2 is uniquely positioned to develop, test, and deploy ambitious, “limit-of-physics” optical and photonic payloads across MEO, GEO, cislunar, and deep space on unprecedented timelines. The satellite bus is the platform – the payloads are the mission.

As a Senior Photonics Engineer focused on free-space optics, your role is to define how K2 measures and models the atmosphere, and how our optical hardware is designed to work through it. You will work at the intersection of free-space optical communications, adaptive optics, and integrated photonics, and own the full loop from experiment to model, across a ladder of experiments: tabletop emulators that reproduce atmospheric turbulence in the lab, benches that put our optical hardware (free-space receivers, wavefront correction, and photonic chips) inside that emulated channel, outdoor links across real turbulence on rooftops and test ranges, and occasional campaigns at mountaintop optical ground stations and observatories. You will own K2's atmospheric channel modeling and decide how measured data flows into requirements for PIC, test, and payload teams. You will work closely with PIC designers, test engineers, and K2's optical payload team, and as K2's payloads grow, you will also consult on remote-sensing and other payloads that look through the atmosphere.

Responsibilities

• Design and build tabletop experiments that emulate optical propagation through turbulent media, using spatial light modulators, phase plates, and phase-screen generation; validate them against target statistics (Cn², r0, scintillation, beam wander, wavefront error, fade statistics).
• Put receivers in the loop (free-space optics, fiber and photonic-chip front ends, and their control electronics) and measure coupling efficiency, fading, bit error rate, and control-loop bandwidth.
• Characterize wavefront sensing and correction hardware (Shack-Hartmann sensors, deformable mirrors, SLMs) alongside photonic-integrated alternatives.
• Take experiments out of the lab: outdoor horizontal-path links on rooftops and test ranges, then night campaigns at mountaintop optical ground stations and observatories, including site coordination, laser-safety approvals, equipment transport, night operations, and data reduction.
• Own K2's optical propagation and channel models long-term: build them in Python, calibrate them continuously against lab and field data, quantify their uncertainty, and turn the results into requirements.
• Define the experiment roadmap: decide which measurements most reduce model uncertainty, and set the lab-to-field test plan.
• Automate experiments on the team's shared test framework so lab and field data share one pipeline.
• Mentor engineers and technicians supporting the experiments.

Qualifications

• Bachelor's degree in optics, physics, electrical engineering, or a related technical field.
• 5+ years of hands-on free-space optics experience in free-space optical communications, adaptive optics, or atmospheric propagation (a relevant PhD counts toward this).
• Led free-space optical experiments end to end: designing and aligning benches, taking data, and correlating it with models.
• Working knowledge of optical turbulence and propagation theory (Cn², Fried parameter, Rytov variance), with Python for modeling and analysis.

Nice to Have

• MS or PhD in optics, physics, or a related field.
• Adaptive optics experience in astronomy, beam control, or free-space optical communications.
• Experience with photonic integrated circuits, photonic lanterns, or fiber coupling through turbulence.
• Pointing, acquisition, and tracking (fast steering mirrors, beacon tracking) or optical link performance analysis (BER, SNR, scintillation and fading).
• Spatial light modulators, deformable or fast steering mirrors, or phase-plate turbulence emulators.
• Field campaigns at an observatory or outdoor optical test range, including night operations.
• Remote sensing, lidar, or atmospheric characterization instruments.
• Wave-optics simulation tools (e.g., AOTools, WaveProp) and Zemax.

Compensation and Benefits:

• Base salary range for this role is $150,000 - $220,000 + equity in the company
• Salary will be based on several factors including, but not limited to: knowledge and skills, education, and experience level
• Comprehensive benefits package including paid time off, medical/dental/vision coverage, life insurance, paid parental leave, and many other perks

If you don’t meet 100% of the preferred skills and experience, we encourage you to still apply! Building a spacecraft unlike any other requires a team unlike any other and non-traditional career twists and turns are encouraged!

If you need a reasonable accommodation as part of your application for employment or interviews with us, please let us know.

Export Compliance

As defined in the ITAR, “U.S. Persons” include U.S. citizens, lawful permanent residents (i.e., Green Card holders), and certain protected individuals (e.g., refugees/asylees, American Samoans). Please consult with a knowledgeable advisor if you are unsure whether you are a “U.S. Person.”

The person hired for this role will have access to information and items controlled by U.S. export control regulations, including the export control regulations outlined in the International Traffic in Arms Regulation (ITAR). The person hired for this role must therefore either be a “U.S. person” as defined by 22 C.F.R. § 120.15 or otherwise eligible for a federally issued export control license.

Equal Opportunity

K2 Space is an Equal Opportunity Employer; employment with K2 Space is governed on the basis of merit, competence and qualifications and will not be influenced in any manner by race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability or any other legally protected status.