We propose a scanning magnetic microscope which has a photoluminescence nanoprobe implanted in the tip of an AFM or STM, or NSOM, and exhibits optically detected magnetic resonance (ODMR). The proposed spin microscope has nanoscale lateral resolution and the single spin sensitivity for AFM and STM.Continuing progress of nanotechnology including spintronics and quantum information processing, based on solid state quantum computer, has brought significant attention to the problem of measurements of magnetic properties of materials with sub-nanometer spatial resolution. The recently developed techniques that demonstrate the highest sensitivity and spatial resolution are magnetic resonance force microscopy (MRFM) and optically detected magnetic resonance (ODMR). Significant progress in MRFM has been made since the first experiment, which was performed at IBM by a team led by Rugar .) The limitation of the lateral resolution of ODMR is related to the size of the light spot. The highest resolution is obtained by a near-field scanning optical microscope (NSOM), which has a light spot size of about 30 -50 nm. Another limitation of the ODMR technique is that the unpaired electron has to be a part of a molecule, which absorbs or emits light.In the present paper we propose a modification of the ODMR technique which is free from the limitations of the conventional ODMR method. In our approach a photoluminescent nanoparticle or other photoluminescent center located in the tip apex exhibits ODMR in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample. We propose several approaches to this spin microscope based on ODMR, the general layouts of which are shown in Fig. 1, 3-5. Fig. 1 presents a design based on the apertureless scanning optical microscope, which exploits the highly sensitive AFM tip modified by implanting a nano-size photoluminescent particle in the apex of the tip. The sample to be observed is located in close proximity to the tip-on-cantilever system, and a permanent magnet is placed nearby. A nearby radio-frequency coil produces an oscillating field at the frequency resonant with the transition between the magnetic sublevels of the photoluminescent nanoparticle. Or another photoluminescent center located in the tip apex exhibits ODMR in the vicinity of unpaired electron spins or nuclear

A new concept of a free-space, high-speed (Gbps) optical communication system based on spectral encoding of radiation from a broadband pulsed laser is developed. It is shown that, in combination with the use of partially coherent laser beams and a relatively slow photosensor, scintillations can be suppressed by orders of magnitude for distances of more than 10 km. We also consider the spectral encoding of radiation from a LED as a gigabit rate solution of the "last mile" problem and rapid-deployment systems for disaster recovery.

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