Laser-heated diamond anvil cell (LH-DAC) experimentation has emerged as a leading technique for materials processing at extreme pressures and temperatures. LH-DAC systems are often employed to better characterise the structure and properties of materials in applications ranging from condensed matter physics to geophysical research to planetary science. This article reviews LH-DAC and related laser-based characterisation, as the first part of a series within the broader context of all high-pressure laser-induced material processing. In part I of this review, a synopsis of laser-heated diamond anvil cell experimental methods, developmental history, fundamental physicochemical processes, and emerging research trends are provided. Important examples of minerals/materials modified during LH-DAC investigations (since their inception) are also tabulated, including key phase transformations, material syntheses, laser parameters, and process conditions—as a reference for the reader and as a guide for directing future research efforts. Note that laser-dynamic-compression within diamond anvil cells (LDC-DAC experimentation) and laser-induced reactive chemical synthesis within diamond anvil cells (LRS-DAC experimentation) are treated separately, as Parts II and III of this review.

The field of high-pressure materials research has grown steadily over the last seven decades, with many remarkable discoveries having been made. This work is part II of a three-part series summarising recent progress in laser material processing within diamond anvil cells (L-DACs); this article focuses on the practice of laser-driven dynamic compression within diamond anvil cells (i.e., LDC–DAC experimentation). In this case, materials are initially pre-compressed within diamond anvil cells, then further dynamically compressed through the use of a high-power pulsed laser, often with the intent to isentropically compress, rather than to heat samples. The LDC–DAC approach provides a novel route to much higher dynamic pressures (approaching 1 TPa), as compared to conventional static compression within a single-stage DAC (<300 GPa) and provides a route to mapping Hugoniot curves. Recent proliferation of low-cost, high-power laser sources has led to increased research activity in LDC–DAC materials processing over the last two decades. Through LDC–DAC experiments, a greater understanding of the properties/structure of cold- and warm-dense matter has been obtained, and novel material phases have been realised. In this article, LDC–DAC experimental methods are reviewed, together with the underlying physics of laser dynamic compression in confined spaces. In addition, a chronology of important events in the development of LDC–DAC processing is provided, and emerging trends, gaps in knowledge, and suggestions for further work are considered.

The synthesis of advanced materials at high pressures has been an area of growing research interest for several decades. This article is the third in a three-part series that reviews Laser Materials Processing Within Diamond Anvil Cells (L-DACs). Part III focuses on the practice of Laser Reactive Synthesis Within Diamond Anvil Cells (LRS-DAC). During LRS-DAC processing, chemicals are precompressed within diamond anvil cells, then microscale chemical reactions are induced by focused laser beams. The method is distinguished from the well-known Laser-Heated Diamond Anvil Cell (LH-DAC) technique (see Part I) through the existence of chemical precursors (reactants), end-products, and quantifiable changes in chemical composition upon reaction. LRS-DAC processing provides at least three new degrees of freedom in the search for advanced materials (beyond adjusting static pressures and temperatures), namely: laser-excitation/cleavage of chemical bonds, time-dependent reaction kinetics via pulsed lasers, and pressure-dependent chemical kinetics. All of these broaden the synthetic phase space considerably. Through LRS-DAC experimentation, it is possible to obtain increased understanding of high-pressure chemical kinetics—and even the nature of chemical bonding itself. Here, LRS-DAC experimental methods are reviewed, along with the underlying chemistry/physics of high-pressure microchemical reactions. A chronology of key events influencing the development of LRS-DAC systems is provided, together with a summary of novel materials synthesised, and unusual chemical reactions observed. Current gaps in knowledge and emerging opportunities for further research are also suggested.