A device for the conversion from a solid state to liquid state of a cryogenic sample contained in a vessel (110;750;880;2001), the device comprising: a pliable solid material (125;760;885;2030;2032) forming a receptacle for receiving the vessel (110;750;880;2001); a non-pliable solid material (120;710;720;810;815;1820;2008;2010) configured to form a cavity, wherein the pliable solid material (125;760;885;2030;2032) forms a lining within the cavity; a heater configured to heat the pliable solid material (125;760;885;2030;2032) through the non-pliable solid material (120;710;720;810;815;1820;2008;2010) to a temperature higher than a melting point of the sample and to radially heat the vessel (110;750;880;2001), when the vessel is in the receptacle, such that a thaw time of contents within the vessel (110;750;880;2001) is predominantly independent of a vessel fill level; a temperature sensor (130;2042) that is fixed in, and thermally insulated from, the non-pliable solid material (120;710;720;810;815;1820;2008;2010), wherein the temperature sensor is configured to be held in contact with the vessel at a contact location or is a non-contact infrared sensor, a temperature signal reported by the temperature sensor (130;2042) being associated with a temperature of an exterior surface of the vessel (110;750;880;2001) when the vessel (110;750;880;2001) is in the receptacle; a microprocessor configured to control the heater; and the microprocessor being configured to deliver a first control signal to interrupt heating at a calculated thaw end time; wherein: the cryogenic sample at the calculated thaw end time has some solid phase remaining in an aqueous solution in the vessel, and the calculated thaw end time is determined using: a time value for the start of a phase change from solid to liquid calculated based on temperature data received from the temperature sensor; and a phase change duration value for the vessel (110;750;880;2001). a pliable solid material (125;760;885;2030;2032) forming a receptacle for receiving the vessel (110;750;880;2001); a non-pliable solid material (120;710;720;810;815;1820;2008;2010) configured to form a cavity, wherein the pliable solid material (125;760;885;2030;2032) forms a lining within the cavity; a heater configured to heat the pliable solid material (125;760;885;2030;2032) through the non-pliable solid material (120;710;720;810;815;1820;2008;2010) to a temperature higher than a melting point of the sample and to radially heat the vessel (110;750;880;2001), when the vessel is in the receptacle, such that a thaw time of contents within the vessel (110;750;880;2001) is predominantly independent of a vessel fill level; a temperature sensor (130;2042) that is fixed in, and thermally insulated from, the non-pliable solid material (120;710;720;810;815;1820;2008;2010), wherein the temperature sensor is configured to be held in contact with the vessel at a contact location or is a non-contact infrared sensor, a temperature signal reported by the temperature sensor (130;2042) being associated with a temperature of an exterior surface of the vessel (110;750;880;2001) when the vessel (110;750;880;2001) is in the receptacle; a microprocessor configured to control the heater; and the microprocessor being configured to deliver a first control signal to interrupt heating at a calculated thaw end time; wherein: the cryogenic sample at the calculated thaw end time has some solid phase remaining in an aqueous solution in the vessel, and the calculated thaw end time is determined using: a time value for the start of a phase change from solid to liquid calculated based on temperature data received from the temperature sensor; and a phase change duration value for the vessel (110;750;880;2001). the cryogenic sample at the calculated thaw end time has some solid phase remaining in an aqueous solution in the vessel, and the calculated thaw end time is determined using: a time value for the start of a phase change from solid to liquid calculated based on temperature data received from the temperature sensor; and a phase change duration value for the vessel (110;750;880;2001). a time value for the start of a phase change from solid to liquid calculated based on temperature data received from the temperature sensor; and a phase change duration value for the vessel (110;750;880;2001).