Lecture on Superfluidity of Light and Its Applications

Introduction

• Dual Properties of Light: Light behaves as both a wave and a stream of photons.
• Recent Discovery: Light can exhibit superfluidity at room temperature.
• Significance: Potentially groundbreaking for energy efficiency in electrical circuits and quantum computers.

Superfluidity

• Definition: A fluid with zero viscosity that flows without kinetic energy loss.
• Characteristics: Forms vortices that rotate indefinitely.
• Examples: Occurs in liquefied isotopes of helium at cryogenic temperatures.
  • Bizarre Properties: Liquid helium can climb container walls.

Liquid Light as a Superfluid

• Concept: Derived from Bose-Einstein Condensate (BEC).
• Bose-Einstein Condensate:
  • Formed when a gas of bosons is cooled below a critical temperature.
  • Bosons occupy the lowest quantum state, revealing quantum mechanical phenomena.
• Challenges: Liquid light typically exists for fractions of a second at near absolute zero temperatures.

Breakthrough by CNR Nanotech (2017)

• Methodology:
  • Used a thin film of organic material (TDAP) between dielectric mirrors.
  • Created a Fabry-Perot microcavity subjected to a 35 femtosecond laser blast.
• Outcome: Achieved room temperature liquid light superfluidity.

Mechanism

• Photon Interaction: Photons interact with electron-hole pairs (excitons).
• Polaritons Formation:
  • Excitons impose a dipole moment that combines with the electromagnetic field.
  • Strong coupling results in polaritons (quasiparticles of half light, half matter).
  • Behave like atoms and undergo Bose-Einstein condensation at room temperature.
• Observation:
  • Used fast detection to observe polariton dynamics.
  • Polaritons flow without friction around obstacles.

Implications

• Ambient Condition Studies: Superfluid condensates studied through tabletop experiments.
• Semiconductor Research:
  • Observed BEC formation in molybdenum disilanide (thinnest semiconductor).
  • Electrically neutral liquid light runs through microcircuits.

Applications

• Polaritonic Devices:
  • Process data at speeds near light speed.
  • Potential game changer for quantum computing.
• Quantum Computing:
  • Current systems operate at extremely cold temperatures to prevent qubit errors.
  • Liquid light power may enable room temperature quantum computing.

Conclusion

• Potential: Liquefied light power holds promise for advancements in technology and computing at room temperature.
• Call to Action: Continued research and exploration can lead to practical applications.
• Engagement: Viewers encouraged to like, share, and subscribe for more insights.