Physical Properties of Materials

Materials exhibit a rich array of physical properties that dictate their suitability for structural, electronic, thermal and functional applications. Mechanical characteristics such as elasticity, plasticity and toughness arise from atomic bonding and crystal structure, governing load-bearing performance. Thermal properties—heat capacity, thermal conductivity and expansion—control temperature gradients, energy storage and dimensional stability across operating regimes. Electronic and dielectric responses, determined by band structure and carrier mobility, underpin conductivity, semiconduction and insulating behaviour. Coupled electromechanical effects such as piezoelectricity and flexoelectricity enable energy conversion between mechanical stress and electric polarisation. Magnetic ordering and magnetocrystalline anisotropy in transition-metal and rare-earth alloys give rise to soft and hard magnetic responses, crucial for data storage and electromechanical actuators. Optical properties, from refractive index to photoluminescence, emerge in semiconductors, insulators and nanostructures, guiding photonic and sensing devices. At the nanoscale, surface-to-volume ratios and quantum confinement further modify these properties, offering new avenues for metamaterials, two-dimensional crystals and composite systems. Understanding the interplay of structure, composition and external stimuli is essential for tailoring materials to demanding environments in energy, transportation, information technology and healthcare.

Research from Nature Portfolio

Converse flexoelectricity has been shown to dominate nanoscale electromechanical measurements in centrosymmetric dielectrics. High-resolution piezoresponse force microscopy revealed that non-uniform electric fields at the probe tip induce measurable strain in materials that lack conventional piezoelectric order. This finding clarifies anomalously large “piezoelectric” signals in non-polar crystals and emphasises the universal role of flexoelectric coupling in nanoscale probes and devices.

Atomic-scale investigation of samarium–cobalt permanent magnets uncovered how cellular nanostructure and dopant content control domain-wall pinning. A diamond-shaped cellular architecture, tuned by Fe, Cu and Zr dopants, governs the density and strength of pinning sites. Detailed correlation between atomic-scale phase arrangement and macroscopic coercivity advances the design of high-temperature, high-energy-product magnets.

Physical Properties of Materials publication trend

The graph below shows the total number of articles in physical properties of materials across all publications each year (not limited to Nature Index journals).

Technical terms

Elastic modulus: The ratio of stress to strain in the linear (elastic) deformation regime, indicating material stiffness.

Thermal expansion coefficient: The fractional change in length or volume per degree change in temperature.

Flexoelectricity: Polarisation generated in a dielectric by non-uniform mechanical strain (strain gradient).

Coercivity: The reverse magnetic field required to reduce a magnet’s net magnetisation to zero.

Band gap: The energy difference between the valence and conduction bands in a semiconductor or insulator.

DFT+U: A computational approach combining density functional theory with a Hubbard U correction to describe strongly correlated electrons in transition-metal or actinide compounds.

References

1. Converse flexoelectricity yields large piezoresponse force microscopy signals in non-piezoelectric materials. Nature Communications (2019).
2. Atomic structure and domain wall pinning in samarium-cobalt-based permanent magnets. Nature Communications (2017).
3. DFT+U study of the structures and properties of the actinide dioxides. Journal of Nuclear Materials (2017).
4. Fundamentals of Flexoelectricity, Materials and Emerging Opportunities Toward Strain‐Driven Nanocatalysts. Small (2024).
5. Flexocatalysis of nanoscale titanium dioxide. Nano Energy (2024).
6. Phonon and Thermal Properties of Thin Films Made from WS2 Mono- and Few-Layer Flakes. The Journal of Physical Chemistry C (2021).