Photon-efficient optical tweezers via wavefront shaping.

Area of Science:

• Physics
• Optics
• Nanotechnology

Background:

• Optical tweezers use light to trap microscale objects non-contact.
• The fundamental limit of three-dimensional (3D) optical trapping stiffness with a fixed photon budget is unknown.
• Achieving optimal trapping stiffness is crucial for precision nanoscale measurements and photon-efficient manipulation of light-sensitive particles.

Purpose of the Study:

• To theoretically and experimentally investigate the optimization of 3D optical trapping stiffness.
• To determine the fundamental limits of confining microparticles using sculpted optical fields.
• To reduce the confinement volume of microspheres in optical traps.

Main Methods:

• Theoretical modeling of microsphere confinement in sculpted optical traps.
• Experimental implementation of a wavefront shaping-inspired strategy.
• Passive suppression of Brownian fluctuations in all directions concurrently.

Main Results:

• Theoretical prediction of one to two orders of magnitude reduction in confinement volume for microspheres.
• Experimental demonstration of order-of-magnitude reductions in microsphere confinement volumes.
• Successful passive suppression of Brownian motion in all directions.

Conclusions:

• Sculpting light fields customizes optical traps for optimized 3D trapping stiffness.
• This approach significantly reduces particle confinement volumes, approaching fundamental limits.
• The findings advance optical control over the mesoscopic realm, enabling enhanced precision measurements and photon-efficient tweezing.