The principle of the so-called "artificial sun" is to add a small amount of hydrogen isotope deuterium or tritium into the vacuum chamber of this device, and use a Transformer-like principle to make it generate a plasma, then increase its density and temperature to cause a fusion reaction. The process generates huge amounts of energy. The "artificial sun" is:. ['Substances composed of hydrogen isotope deuterium or tritium.', 'A vacuum chamber.', 'One device.', 'Substances that produce huge energy during the reaction.']