The nature of this invention encompasses the creation of a capillary gas chromatography (GC) column assembly and a thermal modulator used to heat or cool the column assembly in a very thermally and chromatographically efficient manner. The GC column assembly described herein consists of capillary GC column material, such as fused silica or metal capillary tubing, which is constrained to lie in a flat, ordered, spiral pattern and then encased between two thin opposing surfaces. The resulting column assembly is flat, dimensionally stable and can be very efficiently thermally modulated. The resulting column assembly also takes up very little space, has very little thermal mass, and can be easily and accurately manufactured. The column assembly can be adapted for chromatographic use by affixing it to the surface of a thermal modulator described herein by means of adhesive force or by mechanical compression, and then by attaching the free ends of the exposed column material to the input and output ports of the chromatographic device. The temperature of the thermal modulator and capillary column assembly is to be controlled by the chromatographic device or by standalone temperature controlling electronics. The thermal modulator described herein contains an element for temperature modulation of the capillary column assembly to which it is attached and a temperature sensing element for providing accurate temperature feedback to the controlling electronics. The overall result of this when coupled to a chromatographic device is maximally efficient chemical separations in a small space with minimal power consumption.