In an information recording/playback device adopting multi-value recording, a configuration to limit the size of marks to be recorded on a recording medium only to a predetermined size equal to or smaller than a beam spot size to enable prevention and reduction of crosstalk and crosswrite is implemented. A recording pulse generation unit configured to generate a recording pulse based on a multi-value modulation data, and a data recording unit configured to record the mark on the recording medium on the basis of the recording pulse are included. The data recording unit executes recording processing of setting sizes of all of marks to be recorded on the recording medium to a size equal to or smaller than a spot size at a half (½) level of a maximum value (Pmax) of a two-dimensional light intensity distribution (power profile) of a beam spot, and executes data recording processing of forming recording regions in modes having different densities of recording marks according to the levels of the multi-value modulation data.

In an information recording/playback device adopting multi-value recording, a configuration to limit the size of marks to be recorded on a recording medium only to a predetermined size equal to or smaller than a beam spot size to enable prevention and reduction of crosstalk and crosswrite is implemented. A recording pulse generation unit configured to generate a recording pulse based on a multi-value modulation data, and a data recording unit configured to record the mark on the recording medium on the basis of the recording pulse are included. The data recording unit executes recording processing of setting sizes of all of marks to be recorded on the recording medium to a size equal to or smaller than a spot size at a half (½) level of a maximum value (Pmax) of a two-dimensional light intensity distribution (power profile) of a beam spot, and executes data recording processing of forming recording regions in modes having different densities of recording marks according to the levels of the multi-value modulation data.

Data can be transmitted and represented by signal gaps in a transmission, the gaps having various attributes. In various examples, data points are encoded and represented by the attributes of said signal gaps. Various attributes of such gaps, including duration, pattern, quantity, time, and/or coordination with a gap in another signal can represent data.

Data can be transmitted and represented by signal gaps in a transmission, the gaps having various attributes. In various examples, data points are encoded and represented by the attributes of said signal gaps. Various attributes of such gaps, including duration, pattern, quantity, time, and/or coordination with a gap in another signal can represent data.

Long term optical memory includes a storage medium composed from an array of silicon nanoridges positioned onto the fused silica glass. The array has first and second polarization contrast corresponding to different phase of silicon. The first polarization contrast results from amorphous phase of silicon and the second polarization contrast results from crystalline phase of silicon. The first and second polarization states are spatially distributed over plurality of localized data areas of the storage medium.

A heat-assisted magnetic recording device includes a write pole positionable adjacent a magnetic recording medium and configured to write data to the medium. A near-field transducer is situated proximate the write pole and configured to produce a thermal spot on the medium. A channel circuit is configured to generate a sequence of symbols having a length of nT, where T is a channel clock rate and n is an integer over a predetermined range. A write driver is configured to apply bi-directional write currents to the write pole to record the sequence of symbols at a location of the thermal spot on the medium, wherein a duration of applying the write currents to the write pole by the write driver is dependent on a length of the sequence of symbols and the effective thermal spot size.

An apparatus comprises a write pole for writing data to a magnetic recording medium and a near-field transducer (NFT) optically coupled to a laser source and configured to produce a thermal spot on the medium. A laser driver applies laser operation power (Iop) to the laser source. A channel circuit generates symbols having a length of nT, where T is a channel clock rate and n is an integer. The laser driver applies Iop to the laser source and a write driver applies bi-directional write currents to the write pole to record the symbols at a location of the thermal spot on the medium, wherein a duration of applying Iop to the laser source by the laser driver is dependent on a length of the symbols and the effective thermal spot size.

A data storage device is disclosed comprising a head actuated over a recording medium, wherein the head comprises a laser configured to heat the recording medium. A mode hop map is generated for a write power applied to the laser during a write operation. The write power is applied to the laser during the write operation and the write power is adjusted in response to the mode hop map.

Data can be transmitted and represented by signal gaps in a transmission, the gaps having various attributes. In various examples, data points are encoded and represented by the attributes of said signal gaps. Various attributes of such gaps, including duration, pattern, quantity, time, and/or coordination with a gap in another signal can represent data.

Data can be transmitted and represented by signal gaps in a transmission, the gaps having various attributes. In various examples, data points are encoded and represented by the attributes of said signal gaps. Various attributes of such gaps, including duration, pattern, quantity, time, and/or coordination with a gap in another signal can represent data.