Variable temperature reactor, heater and control circuit for the same

A variable-temperature reactor for hosting a reaction therein, the reactor comprising:

• a reaction cell comprising:
• a plurality of faces defining the reaction cell,
• wherein the reaction cell has a thickness and a width defining a reaction volume, and
• an outer wall bounding a largest area face of the plurality of faces,
• said outer wall having an outer wall thickness;
• a heater comprising:
• a plurality of heater faces,
• a heat-generating heater element, extending across the area of the reaction volume,
• wherein the heat-generating heater element is disposed on a first heater face of the plurality of heater faces,
• wherein the first heater face is in contact with the outer wall of the reaction cell, and
• a heater support, extending across the area of the heat-generating heater element,
• wherein the heater support is disposed on a second heater face of the plurality of faces,
• wherein the second heater face is opposite the first heater face;
• and
• a heat sink in contact with the heater support, such that the heater support provides a thermal resistance between the heat-generating heater element and the heat sink,
• wherein the reaction cell, when filled with reagents comprising a reagent thermal diffusion coefficient, comprises a reaction cell thermal diffusion time across the reaction cell thickness,
• wherein the reaction cell thermal diffusion time is based on the reaction cell thickness and the reagent thermal diffusion coefficient,
• wherein the outer wall has an outer wall thermal diffusion coefficient and an outer wall thermal diffusion time,
• wherein the outer wall thermal diffusion time is based on the outer wall thickness and the outer wall thermal diffusion coefficient, and
• wherein the outer wall thermal diffusion time is less than one second.