Miller Group - Kostia Pokhodnya

Kostia Pokhodnya

Ph.D. Moscow Institute of Physics and Technology



kostia@chemistry.utah.edu


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Magnetic Thin Films

My specific research objectives are to design a new stable magnetic material that can be used as a working element in (a) non-volatile magnetic DRAM chips, and (b) reading and writing devices for data processing.

To achieve this goal one should design a material which:
1) exhibits a substantial spontaneous magnetization at room temperature;

Figure 1. Magnetic thin films of the V[TCNE]_x magnetically order with a magnetic transition at T_c = 370 K, almost 100 ^oC above room temperature.

2) has an almost rectangular hysteresis loop and relatively high coercivity (~1 kOe) for chip applications; (should be done, no fundamental limitations)

3) has vanishing coercivity for reading/writing device applications;

4) can be easily processed into a thin film;
V[TCNE]_x film can be deposited by CVD technique on variety of rigid and flexible substrates: glass, Si wafer, Teflon, gold, silver and aluminum foils, amorphous carbon, etc.

Figure 2. Schematic illustration of the CVD apparatus used to prepare thin films of the V[TCNE]_x magnet.

5) is stable in the open air itself, or, if not very stable, can be shielded in protective layers.
V[TCNE]_x film remains magnetic in air for 1h

Figure 3. Photo of ca. 5 µm film of the V[TCNE]_x magnet on a glass cover slide being attracted to a Co₅Sm magnet (ambient conditions in air).

References:
K.I. Pokhodnya, A.J. Epstein, J.S. Miller, Thin-Film V[TCNE]_x Magnets, Advanced Materials, 12, Issue 6, 410, (2000).

My specific research objectives are to design a new stable magnetic material that can be used as a working element in (a) non-volatile magnetic DRAM chips, and (b) reading and writing devices for data processing. To achieve this goal one should design a material which: 1) exhibits a substantial spontaneous magnetization at room temperature;
	Figure 1. Magnetic thin films of the V[TCNE]_x magnetically order with a magnetic transition at T_c = 370 K, almost 100 ^oC above room temperature.
2) has an almost rectangular hysteresis loop and relatively high coercivity (~1 kOe) for chip applications; (should be done, no fundamental limitations) 3) has vanishing coercivity for reading/writing device applications; 4) can be easily processed into a thin film; V[TCNE]_x film can be deposited by CVD technique on variety of rigid and flexible substrates: glass, Si wafer, Teflon, gold, silver and aluminum foils, amorphous carbon, etc.
Figure 2. Schematic illustration of the CVD apparatus used to prepare thin films of the V[TCNE]_x magnet.
5) is stable in the open air itself, or, if not very stable, can be shielded in protective layers. V[TCNE]_x film remains magnetic in air for 1h
	Figure 3. Photo of ca. 5 µm film of the V[TCNE]_x magnet on a glass cover slide being attracted to a Co₅Sm magnet (ambient conditions in air).
References: K.I. Pokhodnya, A.J. Epstein, J.S. Miller, Thin-Film V[TCNE]_x Magnets, Advanced Materials, 12, Issue 6, 410, (2000).