Laser Cooling Limit Temperature Calculator

How to Use This Calculator

1. Enter the Photon Energy (ε) in electron volts (eV). This is typically the energy of the laser photons used for cooling (e.g., 2.41 eV for a common transition in rubidium atoms).
2. Enter the Particle Mass (m) in kilograms (kg). Use the exact mass of the particle you're cooling (e.g., mass of an electron or atom).
3. The Boltzmann constant (k_B) is provided as a fixed value (1.380649 × 10^-23 J/K) and cannot be changed.
4. Click the Calculate button to compute the laser cooling limit temperature.
5. The result will be displayed in Kelvin (K), showing the maximum temperature that can be achieved through laser cooling for the given parameters.

Working Principle

Laser cooling limits the temperature to which particles can be cooled due to the quantum mechanical nature of photons. The maximum cooling temperature is proportional to the photon energy and inversely proportional to the particle mass:

T_lim = ε / (k_B * γ)

where:

• T_lim is the laser cooling limit temperature
• ε is the photon energy
• k_B is the Boltzmann constant
• γ is a dimensionless cooling parameter (typically around 0.5 for atomic systems)

This formula shows that cooling efficiency increases with photon energy and decreases with particle mass. For example, atoms like rubidium, which are much lighter than molecules, can be cooled to microkelvin temperatures using visible light.

Applications

Laser cooling has numerous applications in physics and technology, including:

• Cooling atoms to microkelvin temperatures for Bose-Einstein condensates
• Creating ultra-cold molecules
• Enhancing precision measurements in atomic clocks
• Developing quantum computing qubits
• Studying quantum degeneracy in gases