This course addresses Near-Field Optics and Atom Optics that are frontier optical sciences. First, we learn the occurrence of light by electric dipoles induced in materials. Second, we study evanescent light that decays exponentially without propagation and near-field light that is localized in a nanometric region, and review a scanning near-field optical microscope with a spatial resolution beyond the diffraction limit. Third, we consider the electric dipole interaction between light and matter and derive the optical Bloch equation with density matrices. Finally, we solve two kinds of forces of light on atoms and describe the laser cooling and trapping of atoms with laser light.
Since the propagative light like a laser beam cannot be focused on a space smaller than a half wavelength due to the diffraction limit, it was difficult to apply light to nano-scale sciences. In order to overcome the diffraction limit, near-field light that keeps staying on a material surface is utilized. Meanwhile, laser cooling of gaseous atoms that move at high speed was developed and the many works have won the Nobel prize including the Bose-Einstein condensation. The cold atoms are applied to studies on the quantum computing such as atom chips and qubits these days. This course cultivates the fundamental knowledges required for nano photonics and atom photonics.
By taking this course, you are able to
(1) understand the mechanism of the occurrence of light in matter,
(2) learn evanescent light and near-field light used in nanophotonics,
(3) acquire the operation of the scanning near-field optical microscope with high spatial resolution beyond the diffraction limit,
(4) apply the optical Bloch equation to solve the light-matter interaction, and
(5) acquire how to control atoms with light.
atom photonics, nano photonics, atom optics, near-field optics, laser cooling, Bose-Einstein condensation
|Intercultural skills||Communication skills||Specialist skills||Critical thinking skills||Practical and/or problem-solving skills|
The lecture is delivered using a lecture note. Do an exercise distributed at the end of each class after class. The example solutions are given next class.
|Course schedule||Required learning|
|Class 1||Occurrence of Light by Electric Dipole||Derive the expression of electric magnetic fields generated by electric dipoles, and illustrate the electric dipole radiation.|
|Class 2||Evanescent Light||Derive the decay length and the electro magnetic fields of evanescent light.|
|Class 3||Occurrence and Detection of Near-Field Light, Near-Field Optical Interaction||Explain the occurrence mechanism and the detection method of near-field light, and solve the near-field condition and the resolution.|
|Class 4||Scanning Near-Field Optical Microscope, Virtual Photons and Yukawa Functions||Explain the mechanism and characteristics of a scanning near-field optical microscope, and understand the virtual photon picture.|
|Class 5||Two-Level System, Electric Dipole Interaction, Spontaneous Emission||Solve the Schrödinger equation for the two-level system, and show the time change of the population.|
|Class 6||Density Matrix, Optical Bloch Equation, Power Broadening and Saturation||Derive the optical Bloch equation with density matrices and solve the stationary solution, and explain the phenomena of power broadening and saturation.|
|Class 7||Dressed Atoms, Forces of Light on Atoms||Solve the energy eigenvalues and the light shifts of dressed atoms, and derive a dipole force and a spontaneous force.|
|Class 8||Reflection and Guidance of Atoms, Laser Cooling, Bose-Einstein Condensation||Explain atom reflection, atom guidance, Doppler cooling, magneto-optical trap, polarization gradient cooling, and Bose-Einstein condensation.|
A lecture note is distributed.
An exercise and the example solution are distributed in each class.
You are assessed by the comprehension of occurrence of light, evanescent light, near-field light, forces of light on atoms, and laser cooling.
The point allocation is 60 % for the final exam, and 40 % for exercises.
Fundamentals of Light and Matter I is needed for this course.